What exactly is Apache Camel?

If you have 5 to 10 minutes, then I generally recommend people to read this Article by Jonathan Anstey -http://java.dzone.com/articles/open-source-integration-apache. Its a well written piece, which gives a brief introduction, and overview what Camel is, and some of its concepts, and then implements a use-case, with code samples.

There is also a free chapter of the Camel in Action book - http://manning.com/ibsen/, which introduces Camel in the first chapter. Jonathan is a co-author on that book with me.

no more about when to use apache camel framework

http://javadeveloperchoiceno1.blogspot.in/2014/07/when-to-use-apache-camel.html

if you want to see  about  WebServices. please read this
http://javadeveloperchoiceno1.blogspot.in/2014/07/faq-webservices.html