IBM 5150
The IBM 5150 was IBM's entry into the personal computer marketplace, the IBM PC. The original configuration was for 64kb of ram, and a tape drive, but could be expanded to include a diskette drive, and a hard disk. Back then, both types of disk drives were of the 5 1/4" full height form factor. IBM made the PC an open standard, publishing not only schematics, but also including a BIOS listing in the technical reference. When people wished to build clones of the IBM PC, IBM would license them for a 5% royalty fee, which not only made the PC a popular platform to clone, but also with the available schematics, allowed for everyone to be pin compatible with the ISA slots, creating a thriving hardware expansion business.
The IBM PC included Microsoft BASIC in ROM, which allowed the PC to function like many of the computers of the time with a simple ROM BASIC. With the addition of a disk drive, OS options included CP/M and MS-DOS at the time of sale.
The IBM PC, also established the 8 bit expansion slot, or ISA bus standard.
The PC was replaced by the wildly popular IBM XT.
