Games like Counter strike?

Hi,
I am playing Counter strike for 4 months & i want to know if there are any games available in market similar to CS?
Please suggest me some PC games for shooting & strategies!

Do you want to say that you want some multi-player games like Counter Strike or you just want shooting games? Please be specific.

I want the both!
If its multiplayer then that will be an add on! :)
Want to try all the nice games available there in the market! Since I never played such games except those I use to play with home Video Games like Duck hunt, supermario Tank & all. Nothing more than those games!

My favorite computer game is counter strike because this is a good time pass for
me

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