I learned programming on an Indian Altair/IMSAI 8080 clone that used the S100 bus in 1978 - the ECIL Micro-78. One memorable weekend was spent trying to debug a

I learned programming on an Indian Altair/IMSAI 8080 clone that used the S100 bus in 1978 - the ECIL Micro-78. One memorable weekend was spent trying to debug an obscure bug which turned out to be single memory location failure in a 16 KByte DRAM board that used Intel 4k DRAMs for the first time. DRAMs had a well-earned reputation for unreliability at that time, but had ~4x the density of SRAM from the same era, so they were more economical. In 1982, I started programming in C for the first time on a Cromemco Z80 box at college, and that one was as bulletproof as it got for a dual 8" floppy box of that era. The importance of a plug-in bus like the S100 was a crucial insight that enabled the PC revolution, and the first wave of the microcomputer revolution happened mainly due to bus compatibility. Eventually, Apple and IBM also used plug-in buses which were essentially simplified or smaller versions of the S100, using signals from the 6502 and 8088 instead. The 16-bit extension of the IBM PC plug-in bus became known as ISA, and ensured its enduring domination even to this day (it's still around as the X-bus inside modern highly-integrated Southbridge ASICs, though it's no longer brought out as an external plug-in bus, except in some legacy industrial PCs).