What is the difference in meaning between "When" and "While"

[kttm19]

I want to find out about how to use "While" and "When".I'm embarrassed to use them so i need a specific and detailed explanation.I am very grateful to receive guidance. I sincerely thank you.

[Delfino]

I want to find out about the use of "while" and "when".
I'm afraid to embarrass myself if I use them wrongly.
So I need a specific and detailed explanation.
I'd be very grateful to receive any guidance.
I sincerely thank you in advance.

http://oxforddictionaries.com/definitio ... hen?q=when

vs.

http://oxforddictionaries.com/definitio ... le?q=while