The AT introduced the 80286 CPUCentral processing unit — the primary chip that executes program instructions. and 16-bit expansion bus to the IBMInternational Business Machines — a major computer and enterprise technology company since the early 20th century. PCPersonal computer — a computer designed for individual use, especially desktop or laptop machines. line — OSOperating system — software that manages hardware and provides services to applications./2 and early Windows protected-mode software targeted this hardware. Clone makers shipped AT-compatible machines that extended the PCPersonal computer — a computer designed for individual use, especially desktop or laptop machines. standard. The model name "AT" (Advanced Technology) set expectations for each generation of PCPersonal computer — a computer designed for individual use, especially desktop or laptop machines. upgrades through the 1990s.

The PCPersonal computer — a computer designed for individual use, especially desktop or laptop machines. AT brought 16-bit computing and the 80286 to the mainstream IBMInternational Business Machines — a major computer and enterprise technology company since the early 20th century.-compatible market.

It extended the open PCPersonal computer — a computer designed for individual use, especially desktop or laptop machines. architecture that software and hardware vendors built on for decades.