A computer can be described as an electronic device, which receives data/information as Input, processes it, stores it and delivers processed data/information as Output.
Computers can carry out billions of actions/ processes per second with accuracy and can store huge amount of data/information. Due to speed of processing of data, reliability and huge data storage capacity, computers have entered in all walks of our lives in one way or the other.
Computers come in various shapes and sizes viz. hand held PDAs, portable note books or lap tops, desktops , servers, main frame computers (a network of computers), super computers etc.
In this tutorial, we have confined ourselves to Personal Computers (PCs), which come in horizontal or Flat bed type CPU box (monitor is placed over CPU box) and tower type CPU box (monitor is placed alongside CPU box) shapes. Due to more space available inside a tower type CPU box for connecting cables etc., the tower type shape has become more popular and horizontal CPU boxes have become outdated.