Lets today talk about the ABC's of WCF. Before we look deeper into WCF, these parts are essential to very concept of any communication framework. Essentially its just a way to get to a resource outside. How do you best describe a reachable resource.
If you try and find a analogy, let's say, you are staying in Roswell, GA. You are a good developer. And you are currently working on some task, that requires a deep knowledge of MAPI. And the only book, who has a treatment of the subject that you are currently intrested in is at Barnes and Nobles, Sunnyvale, California. This is the resource that you need to access and your life depends on it. Some how you say B&N, about your certain interest in the resource, you pay them the money and then they ship it to you.
Lets analyse it a bit more:
a.) B&N is a medium to reach the resource.
b.) The resource has a address,
c.) The resource has to physically transported, medium could be Air/Road/Railway.
d.) The Contract is Unless you pay the required amount, B&N do not ship it to you.
All these points are very important. And resource would not make to the correct destination unless, all of the above are true.
Like wise for a WCF Service the following is true:
a.) WCF acts as a medium for the transaction
b.) Address is location of the resource or Service
c.) Binding takes care of the detail about the mode of transportation of the Bytes across the wires
d.) Contract is the protocol established for the Transaction to be carried out successfully.
These are the basics of the ABC in WCF. Hope I could make it clear.