First Generation Computer(1945-1956)

Major components –Vacuum Tubes
Very slow, large in size, consumed a lot of electronic power
The operating speed was measured in terms of millisecond.
Storage capacity was too small only 1 to 4 Kb
They used machine level programming language.
Few 1st Generation computers-Mark-1 ENIAC, EDVAC, EDSAC, UNIVAC etc.