By the early 21st century, nearly every child in the Western world , and many in other pasts of the world, knew how to use a personal computer. Businesses' information technology departments have gone from using stor eage tapes created by a single computer operator to interconnected networks of employee workstation that store information in a server farm,often somewhere away from the main business site. communication has advanced,from physical postal mail,to telephone fax transmission, to nearly instand taneous digital communication through electronic mail .