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Mac operating systems

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110-538: Mac operating systems were developed by Apple Inc. in a succession of two major series. In 1984, Apple debuted the operating system that is now known as the classic Mac OS with its release of the original Macintosh System Software . The system, rebranded Mac OS in 1997, was pre-installed on every Macintosh until 2002 and offered on Macintosh clones shortly in the 1990s. It was noted for its ease of use, and also criticized for its lack of modern technologies compared to its competitors. The current Mac operating system

220-452: A graphical user interface (GUI) to be sold commercially. It uses a Motorola 68000 CPU clocked at 5 MHz and has 1 MB of RAM. It can be upgraded to 2 MB and later shipped with as little as 512 kilobytes. The CPU speed and model were not changed from the release of the Lisa 1 to the repackaging of the hardware as Macintosh XL. The real-time clock uses a 4-bit integer and the base year

330-428: A system call to perform a block I/O write operation, then the system call might execute the following instructions: While the writing takes place, the operating system will context switch to other processes as normal. When the device finishes writing, the device will interrupt the currently running process by asserting an interrupt request . The device will also place an integer onto the data bus. Upon accepting

440-723: A trash can ; and overlapping windows for multitasking . Before the arrival of the Macintosh in 1984, Apple's history of operating systems began with its Apple II computers in 1977, which run Apple DOS , ProDOS , and GS/OS ; the Apple III in 1980 runs Apple SOS ; and the Lisa in 1983 which runs Lisa OS and later MacWorks XL , a Macintosh emulator . Apple developed the Newton OS for its Newton personal digital assistant from 1993 to 1997. Apple launched several new operating systems based on

550-623: A 12-inch (30 cm) screen. Lisa's printer support includes Apple's Dot Matrix , Daisy Wheel , and ImageWriter dot matrix printers, and Canon 's new color inkjet technology. The original Lisa, later called the Lisa 1, has two FileWare 5.25-inch double-sided variable-speed floppy disk drives, more commonly known by Apple's codename "Twiggy". They have what was then a very high capacity of approximately 871 kB each, but are unreliable and use proprietary diskettes. Competing systems with high diskette data storage have much larger 8" floppy disks, seen as cumbersome and old-fashioned for

660-645: A computer even if they are not compatible with the base operating system. A library operating system (libOS) is one in which the services that a typical operating system provides, such as networking, are provided in the form of libraries and composed with a single application and configuration code to construct a unikernel : a specialized (only the absolute necessary pieces of code are extracted from libraries and bound together ), single address space , machine image that can be deployed to cloud or embedded environments. The operating system code and application code are not executed in separated protection domains (there

770-464: A consumer system. Lisa 1's innovations include block sparing, to reserve blocks in case of bad blocks, even on floppy disks. Critical operating system information has redundant storage, for recovery in case of corruption. The first hardware revision, the Lisa 2, was released in January 1984 and was priced between $ 3,495 and $ 5,495 . It was much less expensive than the original model, and dropped

880-571: A development of MULTICS for a single user. Because UNIX's source code was available, it became the basis of other, incompatible operating systems, of which the most successful were AT&T 's System V and the University of California 's Berkeley Software Distribution (BSD). To increase compatibility, the IEEE released the POSIX standard for operating system application programming interfaces (APIs), which

990-488: A history that is largely independent of the classic Mac OS. It is a Unix -based operating system built on NeXTSTEP and other NeXT technology from the late 1980s until early 1997, when Apple purchased the company and its CEO Steve Jobs returned to Apple. Precursors to Mac OS X include OPENSTEP , Apple's Rhapsody project, and the Mac OS X Public Beta . macOS is based on Apple's open source Darwin operating system , which

1100-484: A large legal settlement was paid. In the twenty-first century, Windows continues to be popular on personal computers but has less market share of servers. UNIX operating systems, especially Linux, are the most popular on enterprise systems and servers but are also used on mobile devices and many other computer systems. On mobile devices, Symbian OS was dominant at first, being usurped by BlackBerry OS (introduced 2002) and iOS for iPhones (from 2007). Later on,

1210-409: A larger, higher-resolution display. Lisa's CPU and the storage system were strained by the complexity of the operating system and applications, especially its office suite , and by the ad hoc protected memory implementation, due to the lack of a Motorola memory management unit . Cost-cutting measures that target the consumer market, and the delayed availability of the 68000 processor and its impact on

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1320-442: A library with no protection between applications, such as eCos . A hypervisor is an operating system that runs a virtual machine . The virtual machine is unaware that it is an application and operates as if it had its own hardware. Virtual machines can be paused, saved, and resumed, making them useful for operating systems research, development, and debugging. They also enhance portability by enabling applications to be run on

1430-598: A machine like the Lisa was still so expensive that it was primarily marketed to individual and small and medium-sized businesses as a groundbreaking new alternative to much bigger and more expensive mainframes or minicomputers such as from IBM , that either require additional, expensive consultancy from the supplier, hiring specially trained personnel, or at least, a much steeper learning curve to maintain and operate. Earlier GUI-controlled personal computers were not mass-marketed; for example, Xerox PARC manufactured its Alto workstation only for Xerox and select partners from

1540-430: A major update annually. It is the basis of Apple's current system software for its other devices – iOS , iPadOS , watchOS , and tvOS . Prior to the introduction of Mac OS X, Apple experimented with several other concepts, releasing different products designed to bring the Macintosh interface or applications to Unix-like systems or vice versa, A/UX , MAE , and MkLinux . Apple's effort to expand upon and develop

1650-447: A malformed machine instruction . However, the most common error conditions are division by zero and accessing an invalid memory address . Users can send messages to the kernel to modify the behavior of a currently running process. For example, in the command-line environment , pressing the interrupt character (usually Control-C ) might terminate the currently running process. To generate software interrupts for x86 CPUs,

1760-486: A marketing consultancy firm to find names to replace "Lisa" and "Macintosh" (at the time considered by Jef Raskin to be merely internal project codenames) and then rejected all of the suggestions. Privately, Hertzfeld and the other software developers used "Lisa: Invented Stupid Acronym", a recursive backronym , and computer industry pundits coined the term "Let's Invent Some Acronym" to fit Lisa's name. Decades later, Jobs told his biographer Walter Isaacson : "Obviously it

1870-455: A particular application's memory is stored, or even whether or not it has been allocated yet. In modern operating systems, memory which is accessed less frequently can be temporarily stored on a disk or other media to make that space available for use by other programs. This is called swapping , as an area of memory can be used by multiple programs, and what that memory area contains can be swapped or exchanged on demand. Virtual memory provides

1980-503: A program does not interfere with memory already in use by another program. Since programs time share, each program must have independent access to memory. Cooperative memory management, used by many early operating systems, assumes that all programs make voluntary use of the kernel 's memory manager, and do not exceed their allocated memory. This system of memory management is almost never seen any more, since programs often contain bugs which can cause them to exceed their allocated memory. If

2090-408: A program fails, it may cause memory used by one or more other programs to be affected or overwritten. Malicious programs or viruses may purposefully alter another program's memory, or may affect the operation of the operating system itself. With cooperative memory management, it takes only one misbehaved program to crash the system. Memory protection enables the kernel to limit a process' access to

2200-440: A program tries to access memory that is not accessible memory, but nonetheless has been allocated to it, the kernel is interrupted (see § Memory management ) . This kind of interrupt is typically a page fault . When the kernel detects a page fault it generally adjusts the virtual memory range of the program which triggered it, granting it access to the memory requested. This gives the kernel discretionary power over where

2310-422: A project at Apple to create an updated version of the classic Mac OS . It was to have introduced protected memory , preemptive multitasking , and new underlying operating system features, yet still be compatible with existing Mac software. They originally planned the follow-up release Gershwin to add multithreading and other advanced features. New features were added more rapidly than they could be completed, and

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2420-573: A replacement for its classic Mac OS in the 1990s led to a few cancelled projects, code named Star Trek , Taligent , and Copland . Although the classic Mac OS and macOS (Mac OS X) have different architectures, they share a common set of GUI principles, including a menu bar across the top of the screen; the Finder shell , featuring a desktop metaphor that represents files and applications using icons and relates concepts like directories and file deletion to real-world objects like folders and

2530-447: A replacement for the classic Mac OS , it was later spun off into a joint venture with IBM as part of the AIM alliance , with the purpose of building a competing platform to Microsoft Cairo and NeXTSTEP . The development process never worked, and has been cited as an example of a project death march . Apple pulled out of the project in 1995 before the code had been delivered. Copland was

2640-467: A significant amount of CPU time. Direct memory access (DMA) is an architecture feature to allow devices to bypass the CPU and access main memory directly. (Separate from the architecture, a device may perform direct memory access to and from main memory either directly or via a bus.) When a computer user types a key on the keyboard, typically the character appears immediately on the screen. Likewise, when

2750-402: A specific moment in time. Hard real-time systems require exact timing and are common in manufacturing , avionics , military, and other similar uses. With soft real-time systems, the occasional missed event is acceptable; this category often includes audio or multimedia systems, as well as smartphones. In order for hard real-time systems be sufficiently exact in their timing, often they are just

2860-454: A text-based appliance computer. Jobs redefined Macintosh as a cheaper and more usable form of Lisa's concepts, and led the skunkworks project with substantial motivation to compete in parallel with the Lisa team. In September 1981, below the announcement of the IBM PC , InfoWorld reported on Lisa, "McIntosh", and another Apple computer secretly under development "to be ready for release within

2970-417: A user moves a mouse , the cursor immediately moves across the screen. Each keystroke and mouse movement generates an interrupt called Interrupt-driven I/O . An interrupt-driven I/O occurs when a process causes an interrupt for every character or word transmitted. Devices such as hard disk drives , solid-state drives , and magnetic tape drives can transfer data at a rate high enough that interrupting

3080-453: A variation of the classic reader/writer problem . The writer receives a pipe from the shell for its output to be sent to the reader's input stream. The command-line syntax is alpha | bravo . alpha will write to the pipe when its computation is ready and then sleep in the wait queue. bravo will then be moved to the ready queue and soon will read from its input stream. The kernel will generate software interrupts to coordinate

3190-454: A year". It described Lisa as having a 68000 processor and 128KB RAM, and "designed to compete with the new Xerox Star at a considerably lower price". In May 1982, the magazine reported that "Apple's yet-to-be-announced Lisa 68000 network work station is also widely rumored to have a mouse ." Apple Confidential said, "Finally, and perhaps most damaging, even before the Lisa began shipping in June,

3300-418: Is interrupted by it. Operating systems are found on many devices that contain a computer – from cellular phones and video game consoles to web servers and supercomputers . In the personal computer market, as of September 2024 , Microsoft Windows holds a dominant market share of around 73%. macOS by Apple Inc. is in second place (15%), Linux is in third place (5%), and ChromeOS

3410-409: Is macOS , originally named Mac OS X until 2012 and then OS X until 2016. It was developed between 1997 and 2001 after Apple's purchase of NeXT . It brought an entirely new architecture based on NeXTSTEP , a Unix system, that eliminated many of the technical challenges that the classic Mac OS faced, such as problems with memory management. The current macOS is pre-installed with every Mac and receives

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3520-562: Is remote direct memory access , which enables each CPU to access memory belonging to other CPUs. Multicomputer operating systems often support remote procedure calls where a CPU can call a procedure on another CPU, or distributed shared memory , in which the operating system uses virtualization to generate shared memory that does not physically exist. A distributed system is a group of distinct, networked computers—each of which might have their own operating system and file system. Unlike multicomputers, they may be dispersed anywhere in

3630-612: Is a UNIX operating system with the Mac OS look and feel . It was not very competitive for its time, due in part to the crowded UNIX market and Macintosh hardware lacking high-end design features present on workstation -class computers. Most of its sales was to the U.S. government , where MacOS lacks POSIX compliance. The Macintosh Application Environment (MAE) is a software package introduced by Apple in 1994 that allows certain Unix -based computer workstations to run Macintosh applications. MAE uses

3740-484: Is a change away from the currently running process. Similarly, both hardware and software interrupts execute an interrupt service routine . Software interrupts may be normally occurring events. It is expected that a time slice will occur, so the kernel will have to perform a context switch . A computer program may set a timer to go off after a few seconds in case too much data causes an algorithm to take too long. Software interrupts may be error conditions, such as

3850-580: Is a small embedded operating system which runs on the Macintosh Coprocessor Platform, an expansion card for the Macintosh. It is a single "overdesigned" hardware platform on which third-party vendors build practically any product, reducing the otherwise heavy workload of developing a NuBus -based expansion card . The first version of the system was ready for use in February 1988. In 1988, Apple released its first UNIX -based OS, A/UX , which

3960-487: Is available under an Apple Academic License Agreement. In April 1984, following the Macintosh launch, Apple introduced MacWorks, a software emulation environment enabling Lisa to run Macintosh System software and applications. MacWorks improved Lisa's market appeal. After the early Macintosh operating system first gained hard disk support, MacWorks also gained access to Lisa's hard disk in September. In January 1985, MacWorks

4070-551: Is based on the XNU kernel and BSD . macOS is the basis for some of Apple's other operating systems, including iPhone OS / iOS , iPadOS , watchOS , tvOS , and visionOS . The first version of the system was released on March 24, 2001, supporting the Aqua user interface . Since then, several more versions adding newer features and technologies have been released. Since 2011, new releases have been offered annually. macOS 10.16's version number

4180-485: Is defined as 1980; the software won't accept any value below 1981, so the only valid range is 1981–1995. The real-time clock depends on a 4   ×   AA-cell NiCd pack of batteries that only lasts for a few hours when main power is not present. Prone to failure over time, the battery packs could leak corrosive alkaline electrolyte and ruin the circuit boards. The integrated monochrome black-on-white monitor has 720   ×   364 rectangular pixels on

4290-422: Is difficult to define, but has been called "the layer of software that manages a computer's resources for its users and their applications ". Operating systems include the software that is always running, called a kernel —but can include other software as well. The two other types of programs that can run on a computer are system programs —which are associated with the operating system, but may not be part of

4400-896: Is in fourth place (2%). In the mobile sector (including smartphones and tablets ), as of September 2023 , Android's share is 68.92%, followed by Apple's iOS and iPadOS with 30.42%, and other operating systems with .66%. Linux distributions are dominant in the server and supercomputing sectors. Other specialized classes of operating systems (special-purpose operating systems), such as embedded and real-time systems, exist for many applications. Security-focused operating systems also exist. Some operating systems have low system requirements (e.g. light-weight Linux distribution ). Others may have higher system requirements. Some operating systems require installation or may come pre-installed with purchased computers ( OEM -installation), whereas others may run directly from media (i.e. live CD ) or flash memory (i.e. USB stick). An operating system

4510-443: Is only a single application running, at least conceptually, so there is no need to prevent interference between applications) and OS services are accessed via simple library calls (potentially inlining them based on compiler thresholds), without the usual overhead of context switches , in a way similarly to embedded and real-time OSes. Note that this overhead is not negligible: to the direct cost of mode switching it's necessary to add

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4620-499: Is supported by most UNIX systems. MINIX was a stripped-down version of UNIX, developed in 1987 for educational uses, that inspired the commercially available, free software Linux . Since 2008, MINIX is used in controllers of most Intel microchips , while Linux is widespread in data centers and Android smartphones. The invention of large scale integration enabled the production of personal computers (initially called microcomputers ) from around 1980. For around five years,

4730-473: Is that they do not load user-installed software. Consequently, they do not need protection between different applications, enabling simpler designs. Very small operating systems might run in less than 10 kilobytes , and the smallest are for smart cards . Examples include Embedded Linux , QNX , VxWorks , and the extra-small systems RIOT and TinyOS . A real-time operating system is an operating system that guarantees to process events or data by or at

4840-435: Is the part of the operating system that provides protection between different applications and users. This protection is key to improving reliability by keeping errors isolated to one program, as well as security by limiting the power of malicious software and protecting private data, and ensuring that one program cannot monopolize the computer's resources. Most operating systems have two modes of operation: in user mode ,

4950-457: The Apple II division upon taking Raskin's project. Newer Lisa models addressed its shortcomings but, even with a major price reduction, the platform failed to achieve sales volumes comparable to the much less expensive Mac. The Lisa 2/10 is the final model, then rebranded as the high-end Macintosh XL . Though the original documentation only refers to it as "The Lisa", Apple officially stated that

5060-520: The Apple III SOS operating system released three years earlier, Lisa's disk operating system also organizes its files in hierarchical directories. File system directories correspond to GUI folders, as with previous Xerox PARC computers from which Lisa borrowed heavily. Lisa was designed around a hard drive, unlike the first Macintosh. Lisa has two main user modes: the Lisa Office System and

5170-423: The Apple III of 1980. Apple sold a total of approximately 10,000 Lisa machines at US$ 9,995 (equivalent to about $ 30,600 in 2023) each, generating total sales of $ 100 million against a development cost of more than $ 150 million . The largest Lisa customer was NASA , which used LisaProject for project management. The Lisa 2 and its Mac ROM -enabled Macintosh XL version are the final two releases in

5280-535: The CP/M (Control Program for Microcomputers) was the most popular operating system for microcomputers. Later, IBM bought the DOS (Disk Operating System) from Microsoft . After modifications requested by IBM, the resulting system was called MS-DOS (MicroSoft Disk Operating System) and was widely used on IBM microcomputers. Later versions increased their sophistication, in part by borrowing features from UNIX. Apple 's Macintosh

5390-496: The INT assembly language instruction is available. The syntax is INT X , where X is the offset number (in hexadecimal format) to the interrupt vector table . To generate software interrupts in Unix-like operating systems, the kill(pid,signum) system call will send a signal to another process. pid is the process identifier of the receiving process. signum is

5500-578: The Macintosh Plus was introduced in 1986. The Lisa operating system features protected memory , enabled by a crude hardware circuit compared to the Sun-1 workstation (c. 1982), which features a full memory management unit. Motorola did not have an MMU (memory-management unit) for the 68000 ready in time, so third parties developed their own. Apple's is also the result of a cost-cutting compromise, with sluggish performance. Based, in part, on elements from

5610-647: The OSF Research Institute and Apple in February 1996 to port Linux to the PowerPC platform, and thus Macintosh computers. In mid 1998, the community-led MkLinux Developers Association took over development of the operating system. MkLinux is short for "Microkernel Linux", which refers to its adaptation of the monolithic Linux kernel to run as a server hosted atop the Mach microkernel version 3.0. The Star Trek project (as in "to boldly go where no Mac has gone before")

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5720-404: The X Window System to emulate a Macintosh Finder -style graphical user interface. The last version, MAE 3.0, is compatible with System 7.5.3 . MAE was published for Sun Microsystems SPARCstation and Hewlett-Packard systems. It was discontinued on May 14, 1998. Announced at the 1996 Worldwide Developers Conference (WWDC), MkLinux is an open source operating system that was started by

5830-546: The desktop metaphor . Steve Jobs visited PARC in 1979 and was absorbed and excited by the revolutionary mouse-driven GUI of the Alto . By late 1979, Jobs successfully negotiated a sale of Apple stock to Xerox, in exchange for his Lisa team receiving two demonstrations of ongoing research projects at PARC. When the Apple team saw the demonstration of the Alto computer, they were able to see in action

5940-462: The original Macintosh on January 24, 1984; its early system software is partially based on Lisa OS , and inspired by the Alto computer, which former Apple CEO Steve Jobs previewed at Xerox PARC . It was originally named "System Software", or simply "System"; Apple rebranded it as "Mac OS" in 1996 due in part to its Macintosh clone program that ended one year later. Classic Mac OS is characterized by its monolithic design. Initial versions of

6050-420: The transistor in the mid-1950s, mainframes began to be built. These still needed professional operators who manually do what a modern operating system would do, such as scheduling programs to run, but mainframes still had rudimentary operating systems such as Fortran Monitor System (FMS) and IBSYS . In the 1960s, IBM introduced the first series of intercompatible computers ( System/360 ). All of them ran

6160-410: The CPU for every byte or word transferred, and having the CPU transfer the byte or word between the device and memory, would require too much CPU time. Data is, instead, transferred between the device and memory independently of the CPU by hardware such as a channel or a direct memory access controller; an interrupt is delivered only when all the data is transferred. If a computer program executes

6270-474: The CPU to re-enter supervisor mode , placing the kernel in charge. This is called a segmentation violation or Seg-V for short, and since it is both difficult to assign a meaningful result to such an operation, and because it is usually a sign of a misbehaving program, the kernel generally resorts to terminating the offending program, and reports the error. Windows versions 3.1 through ME had some level of memory protection, but programs could easily circumvent

6380-420: The Lisa and wrote in February 1983 that it was "the most important development in computers in the last five years, easily outpacing [the IBM PC ]". It acknowledged that the $ 9,995 price was high, and concluded "Apple ... is not unaware that most people would be incredibly interested in a similar but less expensive machine. We'll see what happens". The Lisa was a commercial failure, the company's largest since

6490-430: The Lisa had been hard work. He said the system's hard disk and RAM was a requirement and not a luxury, but that the system remains slow. He noted that, by 1989, Lisa's level of integration between applications had not yet been repeated by Apple. Original "Twiggy" based Lisa 1 systems command high prices at auction due to the scarcity of surviving examples. The auction record for a Lisa 1 was set on September 10, 2024, when

6600-613: The Lisa line, which was discontinued in April 1985. The Macintosh XL is a hardware and software conversion kit to effectively reboot Lisa into Macintosh mode. In 1986, Apple offered all Lisa and XL owners the opportunity to return their computer and pay $ 1,498 , in exchange for a Macintosh Plus and Hard Disk 20 . Reportedly, 2,700 working but unsold Lisa computers were buried in a landfill. The Macintosh project, led by Steve Jobs, borrowed heavily from Lisa's GUI paradigm and directly took many of its staff, to create Apple's flagship platform of

6710-465: The Lisa only had the original seven applications that Apple had deemed enough to "do everything". UniPress Software released UNIX System III for $ 495 (equivalent to $ 1,500 in 2023). Santa Cruz Operation (SCO) published Microsoft Xenix (version 3), a Unix-like command-line operating system for the Lisa 2, and Microsoft's Multiplan 2.1 spreadsheet for Xenix. Other Lisa Xenix apps include Quadratron's Q-Office suite. BYTE previewed

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6820-492: The Lisa, as compared to the earlier Apple II ‍ — ‍ AST offered a 1.5  MB memory board which, when combined with the standard Apple 512  KB memory board, expanded the Lisa to a total of 2 MB of memory, the maximum amount that the MMU can address. Late in the product life of the Lisa, there were third-party hard disk drives, SCSI controllers , and double-sided 3.5-inch floppy-disk upgrades. Unlike

6930-430: The Macintosh project from Jef Raskin , who had conceived it as a sub- $ 1,000 (equivalent to $ 4,200 in 2023) text-based appliance computer in 1979. Jobs immediately redefined Macintosh to be graphical, but as a less expensive and more focused alternative to Lisa. Macintosh's launch in January 1984 quickly surpassed Lisa's underwhelming sales. Jobs began assimilating increasing numbers of Lisa staff, as he had done with

7040-640: The System Software run one application at a time. System 5 introduced cooperative multitasking . System 7 supports 32-bit memory addressing and virtual memory , allowing larger programs. Later updates to the System 7 enable the transition to the PowerPC architecture. The system was considered user-friendly , but its architectural limitations were critiqued, such as limited memory management , lack of protected memory and access controls , and susceptibility to conflicts among extensions . Nine major versions of

7150-470: The Twiggy floppy drives in favor of a single 400K Sony microfloppy . The Lisa 2 has as little as 512 KB of RAM. The Lisa 2/5 consists of a Lisa 2 bundled with an external 5- or 10-megabyte hard drive. In 1984, at the same time the Macintosh was officially announced, Apple offered free upgrades to the Lisa 2/5 to all Lisa 1 owners, by replacing the pair of Twiggy drives with a single 3.5-inch drive, and updating

7260-699: The Workshop. The Lisa Office System is the GUI environment for end users. The Workshop is a program development environment and is almost entirely text-based, though it uses a GUI text editor. The Lisa Office System was eventually renamed 7/7 which refers to the seven supplied application programs: LisaWrite, LisaCalc, LisaDraw, LisaGraph, LisaProject , LisaList, and LisaTerminal. Apple's warranty said that this software works precisely as stated, and Apple refunded an unspecified number of users, in full, for their systems. These operating system frailties, and costly recalls, combined with

7370-534: The application program, which then interacts with the user and with hardware devices. However, in some systems an application can request that the operating system execute another application within the same process, either as a subroutine or in a separate thread, e.g., the LINK and ATTACH facilities of OS/360 and successors . An interrupt (also known as an abort , exception , fault , signal , or trap ) provides an efficient way for most operating systems to react to

7480-440: The basic elements of what constituted a workable GUI. The Lisa team put a great deal of work into making the graphical interface a mainstream commercial product. The Lisa was a major project at Apple, which reportedly spent more than $ 50 million on its development. More than 90 people participated in the design, plus more in the sales and marketing effort, to launch the machine. BYTE magazine credited Wayne Rosing with being

7590-461: The boot ROM and I/O ROM. In addition, the Lisa 2's new front faceplate accommodates the reconfigured floppy disk drive, and it includes the new inlaid Apple logo and the first Snow White design language elements. The Lisa 2/10 has a 10 MB internal hard drive, no parallel port, and a standard configuration of 1 MB of RAM. Developing early Macintosh software required a Lisa   2. There were relatively few third-party hardware offerings for

7700-447: The classic Mac OS were released. The name "Classic" that now signifies the system as a whole is a reference to a compatibility layer that helped ease the transition to Mac OS X . The system was launched as Mac OS X, renamed OS X from 2012—2016, and then renamed macOS as the current Mac operating system that officially succeeded the classic Mac OS in 2001. The system was originally marketed as simply "version 10" of Mac OS, but it has

7810-672: The completion date slipped into the future with no sign of a release. In 1996, Apple canceled the project outright and sought a suitable third-party replacement. Copland development ended in August 1996, and in December 1996, Apple announced that it was buying NeXT for its NeXTSTEP operating system. Operating system An operating system ( OS ) is system software that manages computer hardware and software resources, and provides common services for computer programs . Time-sharing operating systems schedule tasks for efficient use of

7920-453: The computer's memory. Various methods of memory protection exist, including memory segmentation and paging . All methods require some level of hardware support (such as the 80286 MMU), which does not exist in all computers. In both segmentation and paging, certain protected mode registers specify to the CPU what memory address it should allow a running program to access. Attempts to access other addresses trigger an interrupt, which causes

8030-545: The core of macOS , including iOS in 2007 for its iPhone , iPad , and iPod Touch mobile devices and in 2017 for its HomePod smart speakers ; watchOS in 2015 for the Apple Watch ; and tvOS in 2015 for the Apple TV set-top box . The classic Mac OS is the original Macintosh operating system introduced in 1984 alongside the first Macintosh and remained in primary use on Macs until Mac OS X in 2001. Apple released

8140-432: The design process, made the user experience sluggish. The workstation -tier high price and lack of a technical software application library made it a difficult sale for all markets. The IBM PC's popularity and Apple's decision to compete with itself through the lower-priced Macintosh also hindered Lisa's acceptance. In 1982, after Steve Jobs was forced out of the Lisa project by Apple's board of directors, he appropriated

8250-471: The details of how interrupt service routines behave vary from operating system to operating system. However, several interrupt functions are common. The architecture and operating system must: A software interrupt is a message to a process that an event has occurred. This contrasts with a hardware interrupt — which is a message to the central processing unit (CPU) that an event has occurred. Software interrupts are similar to hardware interrupts — there

8360-432: The early to mid-1970s. Development of project "LISA" began in 1978. It underwent many changes and shipped at US$ 9,995 (equivalent to $ 30,600 in 2023) with a five-megabyte hard drive . It was affected by its high price, insufficient software, unreliable FileWare ( codename Twiggy) floppy disks , and the imminent release of the cheaper and faster Macintosh . Only 60,000 Lisa units were sold in two years. Lisa

8470-422: The environment. Interrupts cause the central processing unit (CPU) to have a control flow change away from the currently running program to an interrupt handler , also known as an interrupt service routine (ISR). An interrupt service routine may cause the central processing unit (CPU) to have a context switch . The details of how a computer processes an interrupt vary from architecture to architecture, and

8580-465: The firm that eventually became IDEO. Bruce Daniels was in charge of applications development, and Larry Tesler was in charge of system software. The user interface was designed in six months, after which the hardware, operating system, and applications were all created in parallel. In 1982, Steve Jobs was forced out of the Lisa project, and he appropriated Jef Raskin 's existing Macintosh project. Raskin had conceived and led Macintosh since 1979 as

8690-410: The hardware checks that the software is only executing legal instructions, whereas the kernel has unrestricted powers and is not subject to these checks. The kernel also manages memory for other processes and controls access to input/output devices. The operating system provides an interface between an application program and the computer hardware, so that an application program can interact with

8800-493: The hardware only by obeying rules and procedures programmed into the operating system. The operating system is also a set of services which simplify development and execution of application programs. Executing an application program typically involves the creation of a process by the operating system kernel , which assigns memory space and other resources, establishes a priority for the process in multi-tasking systems, loads program binary code into memory, and initiates execution of

8910-468: The help of Sun Remarketing, Apple disposed of approximately 2,700 unsold Lisa units in a guarded landfill in Logan, Utah , to receive a tax write-off on the unsold inventory. Some leftover Lisa computers and spare parts were available until Cherokee Data (which purchased Sun Remarketing) went out of business. The Lisa was first introduced on January 19, 1983. It is one of the first personal computer systems with

9020-418: The indirect pollution of important processor structures (like CPU caches , the instruction pipeline , and so on) which affects both user-mode and kernel-mode performance. The first computers in the late 1940s and 1950s were directly programmed either with plugboards or with machine code inputted on media such as punch cards , without programming languages or operating systems. After the introduction of

9130-404: The interrupt request, the operating system will: When the writing process has its time slice expired, the operating system will: With the program counter now reset, the interrupted process will resume its time slice. Among other things, a multiprogramming operating system kernel must be responsible for managing all system memory which is currently in use by the programs. This ensures that

9240-431: The kernel—and applications—all other software. There are three main purposes that an operating system fulfills: With multiprocessors multiple CPUs share memory. A multicomputer or cluster computer has multiple CPUs, each of which has its own memory . Multicomputers were developed because large multiprocessors are difficult to engineer and prohibitively expensive; they are universal in cloud computing because of

9350-400: The memory allocated to a different one. Around the same time, teleprinters began to be used as terminals so multiple users could access the computer simultaneously. The operating system MULTICS was intended to allow hundreds of users to access a large computer. Despite its limited adoption, it can be considered the precursor to cloud computing . The UNIX operating system originated as

9460-532: The most important person in the development of the computer's hardware until the machine went into production, at which point he became the technical lead for the entire Lisa project. The hardware development team was headed by Robert Paratore. The industrial design, product design, and mechanical packaging were headed by Bill Dresselhaus, the Principal Product Designer of Lisa, with his team of internal product designers and contract product designers from

9570-530: The much less expensive Mac. The Macintosh project assimilated a lot more Lisa staff. The final revision, the Lisa 2/10, was modified and sold as the Macintosh XL . The high cost and the delays in its release date contributed to the Lisa's discontinuation although it was repackaged and sold at $ 4,995 , as the Lisa 2. In 1986, the entire Lisa platform was discontinued. In 1987, Sun Remarketing purchased about 5,000 Macintosh XLs and upgraded them. In 1989, with

9680-441: The name was an acronym for "Local Integrated Software Architecture". Because Steve Jobs's first daughter was named Lisa (born in 1978), it was sometimes inferred that the name also had a personal association, and perhaps that the acronym was a backronym contrived later to fit the name. Andy Hertzfeld said that the acronym was reverse-engineered from the name "Lisa" in late 1982 by the Apple marketing team after they had hired

9790-408: The need to use it. A general protection fault would be produced, indicating a segmentation violation had occurred; however, the system would often crash anyway. The use of virtual memory addressing (such as paging or segmentation) means that the kernel can choose what memory each program may use at any given time, allowing the operating system to use the same memory locations for multiple tasks. If

9900-477: The next several decades. The column-based interface , for instance, utilized by Mac OS X, had originally been developed for Lisa. It had been discarded in favor of the icon view. Apple's culture of object-oriented programming on Lisa contributed to the 1988 conception of Pink , the first attempt to re-architect the operating system of Macintosh. In 1989, after Wayne Rosing had moved to Sun Microsystems , he reflected on his time at Apple, recalling that building

10010-408: The open-source Android operating system (introduced 2008), with a Linux kernel and a C library ( Bionic ) partially based on BSD code, became most popular. The components of an operating system are designed to ensure that various parts of a computer function cohesively. With the de facto obsoletion of DOS , all user software must interact with the operating system to access hardware. The kernel

10120-429: The original Macintosh, the Lisa has expansion slots. The Lisa 2 motherboard has a very basic backplane with virtually no electronic components, but plenty of edge connector sockets and slots. There are two RAM slots, one CPU upgrade slot, and one I/O slot, all in parallel. At the other end are three Lisa slots in parallel. In January 1985, following the Macintosh, the Lisa 2/10 (with integrated 10 MB hard drive)

10230-421: The piping. Signals may be classified into 7 categories. The categories are: Input/output (I/O) devices are slower than the CPU. Therefore, it would slow down the computer if the CPU had to wait for each I/O to finish. Instead, a computer may implement interrupts for I/O completion, avoiding the need for polling or busy waiting. Some computers require an interrupt for each character or word, costing

10340-448: The press was full of intentionally-leaked rumors about a fall release of a 'baby Lisa' that would work in much the same way, only faster and cheaper. Its name: Macintosh." Lisa was launched on January 19, 1983. Its low sales were quickly surpassed by the January 1984 launch of the Macintosh. Newer versions of the Lisa were introduced that addressed its faults and lowered its price considerably, but it failed to achieve sales comparable to

10450-410: The programmer or the user with the perception that there is a much larger amount of RAM in the computer than is really there. Lisa OS Lisa is a desktop computer developed by Apple , produced from January 19, 1983 to August 1, 1986, and succeeded by Macintosh . It is generally considered the first mass-market personal computer operable through a graphical user interface (GUI). In 1983,

10560-401: The project evolved into the " window-and-mouse-driven " form of its eventual release. Trip Hawkins and Jef Raskin contributed to this change in design. Apple's co-founder Steve Jobs was involved in the concept. At Xerox's Palo Alto Research Center (PARC), research had already been underway for several years to create a new humanized way to organize the computer screen, which became known as

10670-418: The same operating system— OS/360 —which consisted of millions of lines of assembly language that had thousands of bugs . The OS/360 also was the first popular operating system to support multiprogramming , such that the CPU could be put to use on one job while another was waiting on input/output (I/O). Holding multiple jobs in memory necessitated memory partitioning and safeguards against one job accessing

10780-400: The signal number (in mnemonic format) to be sent. (The abrasive name of kill was chosen because early implementations only terminated the process.) In Unix-like operating systems, signals inform processes of the occurrence of asynchronous events. To communicate asynchronously, interrupts are required. One reason a process needs to asynchronously communicate to another process solves

10890-400: The size of the machine needed. The different CPUs often need to send and receive messages to each other; to ensure good performance, the operating systems for these machines need to minimize this copying of packets . Newer systems are often multiqueue —separating groups of users into separate queues —to reduce the need for packet copying and support more concurrent users. Another technique

11000-442: The system and may also include accounting software for cost allocation of processor time , mass storage , peripherals, and other resources. For hardware functions such as input and output and memory allocation , the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or

11110-691: The very high price point, led to the failure of the Lisa in the marketplace. NASA purchased Lisa machines, mainly to use the LisaProject program. In 2018, the Computer History Museum announced it would be releasing the source code for Lisa OS, following a check by Apple to ensure this would not impact other intellectual property. For copyright reasons, this release does not include the American Heritage dictionary. For its 40th anniversary on January 19, 2023, Lisa OS Software version 3.1's source code

11220-473: The world. Middleware , an additional software layer between the operating system and applications, is often used to improve consistency. Although it functions similarly to an operating system, it is not a true operating system. Embedded operating systems are designed to be used in embedded computer systems , whether they are internet of things objects or not connected to a network. Embedded systems include many household appliances. The distinguishing factor

11330-466: Was a secret prototype beginning in 1992, to port the classic Mac OS to Intel -compatible x86 personal computers. In partnership with Apple and with support from Intel, the project was instigated by Novell , which was looking to integrate its DR-DOS with the Mac OS GUI as a mutual response to the monopoly of Microsoft 's Windows 3.0 and MS-DOS. A team consisting of four from Apple and four from Novell

11440-456: Was considered a commercial failure but with technical acclaim, introducing several advanced features that reappeared on the Macintosh and eventually IBM PC compatibles . These include an operating system with memory protection and a document-oriented workflow. The hardware is more advanced overall than the following Macintosh, including hard disk drive support, up to 2  megabytes (MB) of random-access memory (RAM), expansion slots, and

11550-504: Was got the Macintosh Finder and some basic applications such as QuickTime , running smoothly. The project was canceled one year later in early 1993, but was partially reused when porting the Mac OS to PowerPC . Taligent (a portmanteau of "talent" and "intelligent") is an object-oriented operating system and the company producing it. Started as the Pink project within Apple to provide

11660-526: Was named for my daughter." The project began in 1978 as an effort to create a more modern version of the then-conventional design epitomized by the Apple II . A ten-person team occupied its first dedicated office at 20863 Stevens Creek Boulevard next to the Good Earth restaurant, and nicknamed "the Good Earth building". Initial team leader Ken Rothmuller was soon replaced by John Couch , under whose direction

11770-435: Was re-branded MacWorks XL as the primary system application, to convert the Lisa into the Macintosh XL . The launch version of Lisa Office System can not be used for programming, requiring the separate development OS called Lisa Workshop to be toggled and booted. Lisa Workshop was also used to develop Macintosh software for its first few years, until a Macintosh-native development system was released. For most of its lifetime,

11880-491: Was rebranded as Macintosh XL. It was given a hardware and software kit, enabling it to reboot into Macintosh mode and positioning it as the high-end Macintosh. The price was lowered yet again, to $ 4,000, and sales tripled, but CEO John Sculley said that Apple would have lost money increasing production to meet the new demand. Apple discontinued the Macintosh XL, leaving an eight-month void in Apple's high-end product line until

11990-406: Was the first popular computer to use a graphical user interface (GUI). The GUI proved much more user friendly than the text-only command-line interface earlier operating systems had used. Following the success of Macintosh, MS-DOS was updated with a GUI overlay called Windows . Windows later was rewritten as a stand-alone operating system, borrowing so many features from another ( VAX VMS ) that

12100-436: Was updated to 11.0 in the third beta. The third beta version of macOS Big Sur is 11.0 Beta 3 instead of 10.16 Beta 3. An early server computing version of the system was released in 1999 as a technology preview. It was followed by several more official server-based releases. Server functionality has instead been offered as an add-on for the desktop system since 2011. The Apple Real-time Operating System Environment (A/ROSE)

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