The ZX81 was a home computer introduced by Sinclair Research in 1981, designed to be an affordable and accessible entry into personal computing. It was an 8-bit machine, powered by a Zilog Z80 microprocessor running at 3.25 MHz, and featured 1 KB of RAM, though this could be expanded with an external memory module up to 64 KB.
The ZX81 was notable for its minimalist design, with a compact, black plastic case and a rubber membrane keyboard, which was a defining characteristic of Sinclair’s budget computers. It displayed graphics in a resolution of 64×48 pixels and had a limited monochrome colour palette. It connected to a television via a standard RF cable, serving as both the display and the audio output.
Despite its basic specifications, the ZX81 offered a surprisingly powerful range of functionality for its time. It was compatible with a large variety of software, including games, educational programs, and utilities, many of which were distributed on cassette tape. It also featured the Sinclair BASIC programming language, enabling users to write their own programs and code.
Although its performance was basic by modern standards, the ZX81 played a key role in the rise of affordable home computing in the early 1980s and remains an iconic part of computing history. It was particularly popular in the UK and paved the way for subsequent Sinclair computers like the ZX Spectrum.