The term "PC/AT" refers to the IBM Personal Computer/Advanced Technology, introduced by IBM in 1984. It was a significant advancement in personal computing, featuring a 16-bit Intel 80286 processor, which allowed for improved performance and multitasking capabilities compared to earlier models. The PC/AT set a standard for hardware and software compatibility that influenced the design of future personal computers. The PC/AT also introduced the AT bus, which allowed for the connection of additional hardware components, such as graphics cards and storage devices. This expansion capability contributed to the popularity of the PC/AT, making it a foundational model in the evolution of personal computers and leading to the development of the modern PC architecture.