> may i ask what is computer science about?
Yes. See:
http://en.wikipedia.org/wiki/Computer_science

> Is it diffcult?
Yes.

> Do we need to study computer science in order to write a good software like openoffice, mysql, operating system, games
It can help, though opinions vary.

> I VERY CONFUSED TO STUDY WHAT?
What are the choices between which you must choose?


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Don't Stand on your head - you'll get footprints in your hair
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