When were computers used first?

The word ‘computer’ comes from the phrase ‘to compute’, or ‘to calculate’. Tools that help calculations, such as the abacus, have been around for the past 3000 years, but electronic computers that can perform complicated tasks at lightning speed appeared only about 70 year ago. Today, the world can no longer be imagined without computers. We enter commands with the help of keyboards and don’t stop to wonder at phrases like ‘open a window’ with the ‘mouse’. The world of ‘bits and bytes’ is also open to the blind. One has to be careful while downloading information from the Internet because malicious viruses can also be downloaded.