The Rainbow 100 is a personal computer originally released in 1983 and quickly followed by an improved version a year or two later.  This Rainbow is a 100B:

System Stats:

CPU	Intel 8088 Zilog Z80
Memory	896 kB (System Maximum)
Storage	RX50 Dual Floppy Drive (SSQD 400kB)
Display	80x24 or 132x24 characters text
Peripherals	One Serial Port One Serial Printer Port
Operating System	MS-DOS Version 3.10b

The statistics above represent the current host system; other Rainbow's can be quite a bit more powerful, including 800x240x4 graphics, 286 accelerators, clock chips, and MFM hard drives.