CPU- computer processing unit
RAM- Random access Memory
ROM- Read only memory
PDA- Personal digital assistant
CD- Compact Disc
WAN- wide area Network
WWW- world wide web
HTTP- Hypertext...
They are used for many reasons:1. High level computation (Mathmatics)2. Entertainment (probably the biggest)3. Communication (with the internet anything is possible)And4. Education
It is used for jobs , online teaching, research , e-book, training the employs by stimulating and modelling, Microsoft offices (Microsoft word, publisher and PowerPoint)