In third generation computers _________ helps to increase the speed and efficiency of computers.

In fourth generation computers ___________ were used.

Second generation computers were used in __________ period.

The ___________ consisted of hundreds of transistors and other electronic components.

There are historical evidences to prove that Abacus was first used in _________.

In _________, John Napier invented a calculating device called Napier's Bones.

The working principles of today's computers were provided by an English mathematician. 

In __________, Charles Babbage designed a machine called the Analytical Engine.

Abacus was invented around ___________

The third generation of computers used ____________.