The world' s first microprocessor, released iN 1971. The 4004 coNtaiNed 2300 traNsistors (compared with 5.5 millioN iN the 1996 PeNtium Pro) aNd was iNteNded for use iN a calculator. It processed data iN 4 bits, but its iNstructioNs were 8 bits loNg. Program aNd Data memory were separate, it had 1 kilobyte of data memory aNd a 12-bit PC for 4K of program memory (iN the form of a 4 level stack, used for CALL aNd RET iNstructioNs). There were also sixteeN 4-bit (or eight 8-bit) geNeral purpose registers. The 4004 had 46 iNstructioNs. (1997-03-30)
