The IBM PCjr was a home computer produced and marketed by IBM from March 1984 to May 1985, intended as a lower-cost variant of the IBM PC with hardware capabilities better suited for video games, in order to compete more directly with other home computers such as the Apple II and Commodore 64.
The wireless PCjr keyboard
In computing, BIOS is firmware used to provide runtime services for operating systems and programs and to perform hardware initialization during the booting process. The BIOS firmware comes pre-installed on an IBM PC or IBM PC compatible's system board and exists in some UEFI-based systems to maintain compatibility with operating systems that do not support UEFI native operation. The name originates from the Basic Input/Output System used in the CP/M operating system in 1975. The BIOS originally proprietary to the IBM PC has been reverse engineered by some companies looking to create compatible systems. The interface of that original system serves as a de facto standard.
A pair of AMD BIOS chips for a Dell 310 computer from the 1980s. The bottom one shows the distinct window of an EPROM chip.
BIOS chips in a Dell 310 that were updated by replacing the chips
BIOS replacement kit for a Dell 310 from the late 1980s. Included are two chips, a plastic holder for the chips, and a IC extractor.
American Megatrends BIOS 686. This BIOS chip is housed in a PLCC package in a socket.