Is web services a part of web Service?

I have a question: Is web services a part of web server?? And when the client
calls web service, it means that client calls web server??

Or is it a different entity in itself which communicates separately both with
client and server and acts as middleware application..

I am very confused..

Can someone explain me the architecture...???

Thanks..

When you build and deploy your web service, you will deploy it to your web
server.  Typically, you could add in security certificates, etc.  The web
service itself gives applications the ability to work outside of a sandbox model
b/c they can be accessed through different protocols, HTTP probably being the
most popular.

 Hope that helps.