Why use a java programming language?

Its easiness is one advantage in comparison to C/C++ for example. The way it manage memory (no pointers, garbage collector) could be another advantage, because it's easier writing ropust programs in Java. Another good point is the complete framework, Java offers functions for doing about everything. I don't think it's a good language for writing desktopo application or games (flash is better for web-games) but it's good for server because of its good networking funcionalities and threading

The principal advantage is the portability, you can run the same program in all OS, the only one that differs is the virtual machine running in the OS.

I saw people use in promtion their sale refferal. It leads to money.

Java is Platform independent, Java is very best language and very secure for all type of programmings. This Language uses Objects for Programming, OOPs Concept is used in Java.Thanks Dude

maybe because it came from Java island?

I only learnt Java in college. I liked the programming, coz I think it's simple to learn and understand. I like its object oriented concept. I guess we can use java to do many kinds of programs, including web applications. I'm currently using .NET, I find it quite similar to Java's concept. I'd think there are two main lines in programming area, one is .NET, another is Java. It's good to know either of them. If you are interested, you can visit the official Sun MicroSystem website: http://www.sun.com