The ZX81 is a home computer that was produced by Sinclair Research and manufactured in Dundee, Scotland, by Timex Corporation. It was launched in the United Kingdom in March 1981 as the successor to Sinclair's ZX80 and designed to be a low-cost introduction to home computing for the general public. It was hugely successful; more than 1.5 million units were sold. In the United States it was initially sold as the ZX-81 under licence by Timex. Timex later produced its own versions of the ZX81: the Timex Sinclair 1000 and Timex Sinclair 1500. Unauthorized ZX81 clones were produced in several countries.
CP/M, originally standing for Control Program/Monitor and later Control Program for Microcomputers, is a mass-market operating system created in 1974 for Intel 8080/85-based microcomputers by Gary Kildall of Digital Research, Inc. CP/M is a disk operating system and its purpose is to organize files on a magnetic storage medium, and to load and run programs stored on a disk. Initially confined to single-tasking on 8-bit processors and no more than 64 kilobytes of memory, later versions of CP/M added multi-user variations and were migrated to 16-bit processors.
A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PCB). Microcomputers became popular in the 1970s and 1980s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and minicomputers, were comparatively much larger and more expensive. Many microcomputers are also personal computers. An early use of the term "personal computer" in 1962 predates microprocessor-based designs. (See "Personal Computer: Computers at Companies" reference below). A "microcomputer" used as an embedded control system may have no human-readable input and output devices. "Personal computer" may be used generically or may denote an IBM PC compatible machine.
Lisa is a desktop computer developed by Apple, released on January 19, 1983. It is generally considered the first mass-market personal computer operable through a graphical user interface (GUI). In 1983, 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, the Xerox Alto was manufactured only for Xerox and select partners through Xerox PARC from the early to mid-1970s.
The Homebrew Computer Club was an early computer hobbyist group in Menlo Park, California, which met from March 1975 to December 1986. The club had an influential role in the development of the microcomputer revolution and the rise of that aspect of the Silicon Valley information technology industrial complex.
The Altair 8800 is a microcomputer designed in 1974 by MITS and based on the Intel 8080 CPU. Interest grew quickly after it was featured on the cover of the January 1975 issue of Popular Electronics and was sold by mail order through advertisements there, in Radio-Electronics, and in other hobbyist magazines. According to Harry Garland, the Altair 8800 was the product that catalyzed the microcomputer revolution of the 1970s. It was the first commercially successful personal computer. The computer bus designed for the Altair was to become a de facto standard in the form of the S-100 bus, and the first programming language for the machine was Microsoft's founding product, Altair BASIC.
Microsoft BASIC is the foundation software product of the Microsoft company and evolved into a line of BASIC interpreters and compiler(s) adapted for many different microcomputers. It first appeared in 1975 as Altair BASIC, which was the first version of BASIC published by Microsoft as well as the first high-level programming language available for the Altair 8800 microcomputer.
The Kansas City standard (KCS), or Byte standard, is a data storage protocol for standard cassette tapes at 300 bits per second. It originated in a symposium sponsored by Byte magazine in November 1975 in Kansas City, Missouri to develop a standard for the storage of digital microcomputer data on inexpensive consumer quality cassettes. The first systems based on the standard appeared in 1976.
"An Open Letter to Hobbyists" is a 1976 open letter written by Bill Gates, the co-founder of Microsoft, to early personal computer hobbyists, in which Gates expresses dismay at the rampant software piracy taking place in the hobbyist community, particularly with regard to his company's software.
The history of computing hardware starting at 1960 is marked by the conversion from vacuum tube to solid-state devices such as transistors and then integrated circuit (IC) chips. Around 1953 to 1959, discrete transistors started being considered sufficiently reliable and economical that they made further vacuum tube computers uncompetitive. Metal–oxide–semiconductor (MOS) large-scale integration (LSI) technology subsequently led to the development of semiconductor memory in the mid-to-late 1960s and then the microprocessor in the early 1970s. This led to primary computer memory moving away from magnetic-core memory devices to solid-state static and dynamic semiconductor memory, which greatly reduced the cost, size, and power consumption of computers. These advances led to the miniaturized personal computer (PC) in the 1970s, starting with home computers and desktop computers, followed by laptops and then mobile computers over the next several decades.
The IMSAI 8080 is an early microcomputer released in late 1975, based on the Intel 8080 and S-100 bus. It is a clone of its main competitor, the earlier MITS Altair 8800. The IMSAI is largely regarded as the first "clone" microcomputer. The IMSAI machine runs a highly modified version of the CP/M operating system called IMDOS. It was developed, manufactured and sold by IMS Associates, Inc.. In total, between 17,000 and 20,000 units were produced from 1975 to 1978.
Micro Instrumentation and Telemetry Systems (MITS) was an American electronics company founded in Albuquerque, New Mexico that began manufacturing electronic calculators in 1971 and personal computers in 1975.
Processor Technology Corporation was a personal computer company founded in April 1975, by Gary Ingram and Bob Marsh in Berkeley, California. Their first product was a 4K byte RAM board that was compatible with the MITS Altair 8800 computer but more reliable than the MITS board. This was followed by a series of memory and I/O boards including a video display module.
The history of the personal computer as a mass-market consumer electronic device began with the microcomputer revolution of the 1970s. A personal computer is one intended for interactive individual use, as opposed to a mainframe computer where the end user's requests are filtered through operating staff, or a time-sharing system in which one large processor is shared by many individuals. After the development of the microprocessor, individual personal computers were low enough in cost that they eventually became affordable consumer goods. Early personal computers – generally called microcomputers – were sold often in electronic kit form and in limited numbers, and were of interest mostly to hobbyists and technicians.
A personal computer, often referred to as a PC, is a computer designed for individual use. It is typically used for tasks such as word processing, internet browsing, email, multimedia playback, and gaming. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or technician. Unlike large, costly minicomputers and mainframes, time-sharing by many people at the same time is not used with personal computers. The term home computer has also been used, primarily in the late 1970s and 1980s. The advent of personal computers and the concurrent Digital Revolution have significantly affected the lives of people in all countries.
The MRB Z 1013 was an East German single-board computer produced by VEB Robotron Riesa, which was primarily intended for private use and educational institutions. It was powered by a U880 processor and sold together with a membrane keyboard. Initially, the kit was equipped with 16 kilobytes of DRAM, which was later replaced by a 64 KB version.
Home computers were a class of microcomputers that entered the market in 1977 and became common during the 1980s. They were marketed to consumers as affordable and accessible computers that, for the first time, were intended for the use of a single, non-technical user. These computers were a distinct market segment that typically cost much less than business, scientific, or engineering-oriented computers of the time, such as those running CP/M or the IBM PC, and were generally less powerful in terms of memory and expandability. However, a home computer often had better graphics and sound than contemporary business computers. Their most common uses were word processing, playing video games, and programming.
