1st Generation Computers:
First generation of computers started with using vacuum tubes as the basic components for memory and circuitry for CPU (Central Processing Unit).
Features :-
• Vacuum tube technology
• Unreliable
• Supported Machine language only
• Very costly
• Generate lot of heat
• Slow Input/Output device
• Huge size
• Need of A.C.
• Non-portable
• Consumed lot of electricity
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