A nibble is 4 bits. Was used back when I was in college. They started with 4 bit microprocessors... 4004 and 4040 were two of them. They never made much of a hit.
The Intel 8008, Motorola 6800 and the 6502 (improved knock off of the 6800 from a company I can't remember) really kicked microcomputing off.
Ahh, writing assembly code, then converting it to machine code by hand and debugging using a teletype. The good old days. (NOT!)
Semi interesting historical foot note. The Jap's developed the first microprocessor for an american company that wanted to use it as a hand held calculator chip. It was too slow so they abandoned it...