any how that did not help me fcrom any where.. i need small explanation,,,,,,
and when we use each one and for what
Why don't you read the documentation for these classes? That is exactly it, a small description/explanation of what they do and what are their methods. It really doesn't make us want to help you when you won't even go to small lengths to help yourself.
After reading the documentation if you still have more specific questions that the documenation can't explain (perhaps look things up ... google is your friend) you can then come back here with those questions and we will help you further.
Someone went out of their way to help you and you basically said that's not EXACTLy what I wanted, so go try again!
Good luck,
-blazed