Good Day boyatdelhi!
I see you have been mistreated to some rather harsh and insulting responses here. I think its regrettable that one can be made to feel like a criminal for asking a question!
Anyway, although I am very, very far from an authority on these matters, it is my understanding that both human beings (or homo sapiens sapiens) and the ape family evolved from a common ancestor. This common ancestor is sometimes called the "Missing Link."
This refers to the somewhat mysterious creature that "linked" apes and human beings -- the one creature (not single creature but single "family" of creatures) out of which emerged human beings and the ape family. Its actually quite fascinating.
This "Missing Link," through various studies, was shown to have had physical characteristics which, in RETROSPECT, would come to be understood as, HAVING BEEN, "ape-like" and "human-like." This creature, which spawned both humans and apes and monkeys, had both "human" and "apelike" physical characteristics BEFORE humans and apes and monkeys appeared on the scene.
Now this means (and this part can be tricky) that our existence, our human existence was, in fact, not at all dependant upon the existence of apes and monkeys. That is to say that starting from this "Missing Link" the pathway of the apes and monkeys could have just as easily been "cut out," if you will -- and you could have just had us human beings without apes and monkeys coming into existence at all (under the "right" geological, environmental circumstances and all that).
In other words, "fate" and environmental circumstances could have just as easily "colluded," if you will, to EMPHASIZE the prior "human" characteristics of this ancestral "Missing Link" creature; and DE-EMPHASIZE the prior "ape-like" characteristics.
The pendulum could have just as easily swung the other way, as it were. Environmental circumstances could have colluded in such a way as to EMPHASIZE the prior "ape-like" characteristics of the ancestral Missing Link creature; and DE-EMPHASIZE prior "human-like" characteristics of this creature, so the only apes and monkeys emerged without us human beings.
Now, it just so happens that the world was big enough and circumstances permitted the separate expression of both the "human" and "ape" characteristics of the Missing Link.
Take it easy.