What is the adventage of touch typing?

Touch typing is to type without looking into the keys with all fingers. The adventage of this is the work on computers will be easier and one can finish his job quicker.

Without knowing touch-typing skill one should not try to learn computers or get into computer related job.

I 100% disagree with the above - touch typing is not a necessary skill, however it does help. You can still type at a reasonable speed with two fingers, just nowhere near as quickly or accurately as a touch typist.