First generation computers (1945 — 1955)
- It was very bulky
- It was costly
- It uses vacuum tubes as the basis for budding the logic part of computer.
- Its performance was very low.
- The circuit consists of wires and thermionic valves,
- Magnetic drum is used for primary storage of data.
- It uses machine language.
Examples of First generation are: (a) EDSAC (b) EDVAC (c) ACE (d) UNIVAC (e) IBM 700 series.