link

http://www.cs.nott.ac.uk/~ef/ComputerXHistory/EarlyHistory/index.htm

Guys this link is very Useful

We had a meeting to dividing the duration of computer,
we use some references as well. for example,

http://www.computerhope.com/history/1800.htm

we decided to  start our work with this schedule
Sanaz and Sara will work on these four years

1900-1940 1940-1960

1960-1980

1980-1990

And Danoosh, Amir and Arina will work on
1990-2000
 2000-2002
2000-2005
2005-2010