The IBM Personal Computer, also known by its model number "5150" or simply as "IBM PC", is a personal computer released by International Business Machines on 12 August, 1981. The IBM PC is considered one of History's most important computers, since it established the "PC-compatible" platform standard and popularised aspects such as DOS operating systems, interchangeable expansion cards and the x86 CPU architecture.
Originally mounting an Intel 8088 processor, either the IBM Monochrome Display Adapter or the Color Graphics Adapter video cards, a simple internal loudspeaker that established the "PC speaker" audio standard and optionally one or two 5.25-inches floppy disk drives (while also sporting a cassette tape deck connection for data storage), the PC could run IBM PC-DOS 1.0, CP/M-86 or UCSD p-System from floppy, although the greatest support was for the former, which later evolved into an elaborate family of compatible systems.