Computers in the 1970s and early 1980s saw the dominance of mainframes for large organizations, the rise of minicomputers for smaller tasks, and the revolutionary introduction of microprocessors. The Altair 8800, released in 1975, is credited with sparking the personal computer revolution. The Apple II, introduced in 1977, and the IBM PC in 1981, became iconic in the consumer market and business computing, respectively. Home computers like the Commodore VIC-20, Commodore 64, Atari 400/800 series, and Tandy TRS-80 Color Computer gained popularity for gaming, education, and home use. Operating systems such as CP/M and MS-DOS provided the interface for users and software applications. This era laid the foundation for the modern computing landscape.