Java is a programming language, which is Secure, Portable, Multithreaded, Interpreted, Dynamic and Platform Independent. It is widely used for developing Java applications in laptops, data centers, game consoles, scientific supercomputers, cell phones, etc. It is considered as one of the fast, secure, and reliable programming languages preferred by most organizations to build their projects. A Java Programmer writes a program in a human-readable language called Source Code. Therefore, the CPU or Chips never understand the source code written in any programming language. Java code is compiled into intermediate format (bytecode), which can be executed on any systems for which Java virtual machine is ported. That means you can write a Java program once and run it on Windows, Mac, Linux or Solaris without re-compiling.