First generation computers

There has been a continuous advancement occurred in computer systems and many generations of computers came into existence as per the advancements facilitated. The first generation computers were made of vacuum tubes and relays. They were bulky and big in size and unreliable because many vacuum tubes burned out during operations. These also generated a greater amount of heat and having lower internal storage capacity.

They were slow in processing and low speed input output devices. They also required more electrical power and were very costly also.

They consumed a large amount of power on start up and shutting down. These are universal Automatic Computer. The input and output units were the punched card readers and the card punches. These were used in 1940 and ran till 1956 with magnetic drum memory and punched cards for input and output. It was intended both for business and scientific applications.