regarding com classes in vb

[shayer]

Can someone help me as want to know about call-back methods
and how to implement it.Can we implement it in activexdll
or it can be implemented only in case of activexexe.
Did anybody have good idea about following:
1.CollectionClassses
2.Idispatch interface in details

Also i need a precise defination (for interview purpose)for following:
Plz don\'t send the details a i m already familiar but some time my mind get
stuck and i have no answer for such basic questions though i have the concept
but some time not find words to explain.

1.binding
2.Early binding
3.Late Binding
4.EarlyID binding
5.Interface
6.Threads
7.Proxy & Stub Dlls
8.Object Persistence
9.New Vs Create Object
10.COM definition(The best way to describe in short)
11.Component
12.Implements (statement)
13.Thread Pool