The IBM PC
On August 12, 1981, IBM released the IBM Personal Computer. The IBM PC used the then-new Intel 8088 processor. Like other 16-bit CPUs, it could access up to 1 megabyte of RAM, but it used an 8-bit-wide data bus to memory and peripherals. This design allowed use of the large, readily available, and relatively inexpensive family of 8-bit-compatible support chips. IBM decided to use the Intel 8088 after first considering the Motorola 68000 and the Intel i8086, because the other two were considered to be too powerful for their needs. IBM's reputation in business computing, combined with a rapid marketplace of third-party peripherals and the later introduction of IBM PC compatibles from other vendors, allowed the IBM PC architecture to take a substantial market share of business applications.
Many other companies at the time were also making "business personal computers" using their own proprietary designs, some still using 8-bit microprocessors. The ones that used Intel x86 processors often used MS-DOS or CP/M-86, just as 8-bit systems with an Intel 8080 compatible CPU normally used CP/M.
Read more about this topic: Influence Of The IBM PC On The Personal Computer Market