The term bozo bit has been used in two contexts. Initially a weak copy protection system in the 1980s Apple classic Mac OS, the term "flipping the bozo bit" was later reused to describe a decision to ignore a person's input. It is a whimsical term, possibly derived from the classic children's comedy character, Bozo the Clown.
In early versions of Apple's classic Mac OS, the "bozo bit" (also called the "no copy" flag in some documentation) was one of the flags in the Finder Information Record, which described various file attributes. When the bit was set, the file could not be copied. It was called the bozo bit because it was copy protection so weak that only a bozo would think of it, and only a bozo would be deterred by it. Version 5.0 of Finder began ignoring this bit. [1] [2]
The cassette and ROM filing systems [3] and the Advanced Disc Filing System [4] of Acorn MOS feature a rudimentary copy protection mechanism where a file with a certain flag set cannot be loaded except to execute it.
The Compact Disc has a similar "no copy" bit in the subcode, but nearly all disc-copying software ignores it, and usually removes it on copies. Consumer-grade dedicated hardware audio disc copiers usually honor the bozo bit, and will refuse to copy a disc with the bit set. Professional disc copiers ignore the bozo bit and will copy a protected disc.
In his 1995 book Dynamics of Software Development, [5] which presented a series of rules about the political and interpersonal forces that drive software development, Jim McCarthy applied the bozo bit notion to the realm of human interaction. [6] [7]
In his book, McCarthy's rule #4 is "Don't Flip The Bozo Bit". His reasoning is that everyone has something to contribute – it's easy and tempting, when someone ticks a person off or is mistaken (or both), to simply disregard all their input in the future by setting the "bozo flag" to TRUE for that person. But by taking that lazy way out, the person poisons team interactions and cannot avail themselves of help from the "bozo" ever again. [6]
A disk operating system (DOS) is a computer operating system that resides on and can use a disk storage device, such as a floppy disk, hard disk drive, or optical disc. A disk operating system provides a file system for organizing, reading, and writing files on the storage disk, and a means for loading and running programs stored on that disk. Strictly speaking, this definition does not include any other functionality, so it does not apply to more complex OSes, such as Microsoft Windows, and is more appropriately used only for older generations of operating systems.
The history of the graphical user interface, understood as the use of graphic icons and a pointing device to control a computer, covers a five-decade span of incremental refinements, built on some constant core principles. Several vendors have created their own windowing systems based on independent code, but with basic elements in common that define the WIMP "window, icon, menu and pointing device" paradigm.
Hierarchical File System (HFS) is a proprietary file system developed by Apple Inc. for use in computer systems running Mac OS. Originally designed for use on floppy and hard disks, it can also be found on read-only media such as CD-ROMs. HFS is also referred to as Mac OS Standard, while its successor, HFS Plus, is also called Mac OS Extended.
BBC BASIC is an interpreted version of the BASIC programming language. It was developed by Acorn Computers Ltd when they were selected by the BBC to supply the computer for their BBC Literacy Project in 1981.
The Finder is the default file manager and graphical user interface shell used on all Macintosh operating systems. Described in its "About" window as "The Macintosh Desktop Experience", it is responsible for the launching of other applications, and for the overall user management of files, disks, and network volumes. It was introduced with the Macintosh 128K—the first Macintosh computer—and also exists as part of GS/OS on the Apple IIGS. It was rewritten completely with the release of Mac OS X in 2001.
GS/OS is an operating system developed by Apple Computer for its Apple IIGS personal computer. It provides facilities for accessing the file system, controlling input/output devices, loading and running program files, and a system allowing programs to handle interrupts and signals. It uses ProDOS as its primary filing system. GS/OS is a component of Apple IIGS System Software versions 4.0 through 6.0.1, and was the first true 16-bit operating system for the IIGS.
Historically, the classic Mac OS used a form of memory management that has fallen out of favor in modern systems. Criticism of this approach was one of the key areas addressed by the change to Mac OS X.
MultiFinder is an extension for the Apple Macintosh's classic Mac OS, introduced on August 11, 1987 and included with System Software 5. It adds cooperative multitasking of several applications at once – a great improvement over the previous Macintosh systems, which can only run one application at a time. With the advent of System 7, MultiFinder became a standard integrated part of the operating system and remained so until the introduction of Mac OS X.
System 6 is the sixth major release of the classic Mac OS operating system for Macintosh computers, made by Apple Computer. It was released in 1988. It is a monolithic operating system, with cooperative multitasking based on an improved MultiFinder. The boxed version cost US$49, and it was included with all new Macintosh computers until 1991, when it was succeeded by System 7.
Mac OS 8 is the eighth major release of the classic Mac OS operating system for Macintosh computers, released by Apple Computer on July 26, 1997. It includes the largest overhaul of the classic Mac OS experience since the release of System 7, approximately six years before. It places a greater emphasis on color than prior versions. Released over a series of updates, Mac OS 8 represents an incremental integration of many of the technologies which had been developed from 1988 to 1996 for Apple's overly ambitious OS named Copland. Mac OS 8 helped modernize the Mac OS while Apple developed its next-generation operating system, Mac OS X.
Connectix Corporation was a software and hardware company that released innovative products that were either made obsolete as Apple Computer incorporated the ideas into system software, or were sold to other companies once they became popular. It was formed in October 1988 by Jon Garber; the dominant board members and co-founders were Garber, Bonnie Fought, and close friend Roy McDonald. McDonald was still Chief Executive Officer and president when Connectix finally closed in August 2003.
Econet was Acorn Computers's low-cost local area network system, based on a CSMA-CD serial protocol carried over a five-wire data bus, intended for use by schools and small businesses. It was widely used in those areas, and was supported by a large number of different computer and server systems produced both by Acorn and by other companies.
The BBC Master is a home computer released by Acorn Computers in early 1986. It was designed and built for the British Broadcasting Corporation (BBC) and was the successor to the BBC Micro Model B. The Master 128 remained in production until 1993.
The Disc Filing System (DFS) is a computer file system developed by Acorn Computers, initially as an add-on to the Eurocard-based Acorn System 2.
In computing, preemption is the act of temporarily interrupting an executing task, with the intention of resuming it at a later time. This interrupt is done by an external scheduler with no assistance or cooperation from the task. This preemptive scheduler usually runs in the most privileged protection ring, meaning that interruption and then resumption are considered highly secure actions. Such changes to the currently executing task of a processor are known as context switching.
The Machine Operating System (MOS) or OS is a discontinued computer operating system (OS) used in Acorn Computers' BBC computer range. It included support for four-channel sound, graphics, file system abstraction, and digital and analogue input/output (I/O) including a daisy-chained expansion bus. The system was single-tasking, monolithic and non-reentrant.
The sideways address space on the Acorn BBC Microcomputer, Electron and Master-series microcomputer was Acorn's bank switching implementation, providing for permanent system expansion in the days before hard disk drives or even floppy disk drives were commonplace. Filing systems, application and utility software, and drivers were made available as sideways ROMs, and extra RAM could be fitted via the sideways address space.
The BBC Microcomputer System, or BBC Micro, is a series of microcomputers designed and built by Acorn Computers Limited in the 1980s for the Computer Literacy Project of the BBC. The machine was the focus of a number of educational BBC TV programmes on computer literacy, starting with The Computer Programme in 1982, followed by Making the Most of the Micro, Computers in Control in 1983, and finally Micro Live in 1985.
The Advanced Disc Filing System (ADFS) is a computing file system unique to the Acorn computer range and RISC OS-based successors. Initially based on the rare Acorn Winchester Filing System, it was renamed to the Advanced Disc Filing System when support for floppy discs was added and on later 32-bit systems a variant of a PC-style floppy controller.
Mac OS is the series of operating systems developed for the Macintosh family of personal computers by Apple Computer, Inc. from 1984 to 2001, starting with System 1 and ending with Mac OS 9. The Macintosh operating system is credited with having popularized the graphical user interface concept. It was included with every Macintosh that was sold during the era in which it was developed, and many updates to the system software were done in conjunction with the introduction of new Macintosh systems.