I am little bit confused with the thread concept. What does the thread mean in Java. Can any one help me out to understand the Single thread and Multi threading Concepts. If Possible point me out to Tutorial.
Concepts? A single threaded program executes one stream of instructions, one at a time. A multithreaded program seems to (or in the case of a multiprocessor machine, actually does) execute multiple streams of instructions at the same time. That's about it.
There are special APIs to let threads communicate with one another, and for threads to coordinate their activities so that data they share doesn't get corrupted. But there are just details. See here to start learning them.