The IBM PC was the original personal computer platform whose hardware, BIOS, and software conventions became a de facto standard for countless compatible systems. In practice, “IBM PC” often means the whole compatibility model: x86 processors, PC-style boot behavior, standard peripheral interfaces, and operating systems designed to run on that architecture.
In cyber security, that compatibility ecosystem matters because attackers and defenders both rely on it. Malware may target the boot chain, BIOS settings, master boot record, or other legacy PC behaviors that still exist in modern systems for compatibility. Defenders also need to understand IBM PC assumptions when analyzing old disk images, DOS-era tools, firmware-based persistence, or virtual machines that emulate PC hardware. The term is historical, but its design choices still shape how trusted code starts, how recovery works, and where early compromise can hide.