Java is a high-level programming language originally developed by Sun Microsystems and released in 1995.
Java runs on a variety of platforms, such as Windows, Mac OS, and the various versions of UNIX.
This tutorial gives a complete understanding on Java.

History of Java

James Gosling initiated the Java language project in June 1991 for use in one of his many set-top box projects. The language, initially called Oak after an oak tree that stood outside Gosling's office, also went by the name Green and ended up later renamed as Java, from a list of random words.
Sun released the first public implementation as Java 1.0 in 1995. It promised Write Once, Run Anywhere (WORA), providing no-cost run-times on popular platforms.
On 13 November 2006, Sun released much of Java as free and open source software under the terms of the GNU General Public License (GPL).
On 8 May 2007 Sun finished the process, making all of Java's core code free and open-source, aside from a small portion of code to which Sun did not hold the copyright.

Java programming language was originally developed by Sun Microsystems, which was initiated by James Gosling and released in 1995 as core component of Sun Microsystems.s Java platform (Java 1.0 [J2SE]).
As of December 08 the latest release of the Java Standard Edition is 6 (J2SE). With the advancement of Java and its wide spread popularity, multiple configurations were built to suite various types of platforms. Ex: J2EE for Enterprise Applications, J2ME for Mobile Applications.
Sun Microsystems has renamed the new J2 versions as Java SE, Java EE and Java ME respectively. Java is guaranteed to be Write Once, Run Anywhere

A Revised Version of Hello World

import java.io.*; 
class MyFirstProgram {
  /** Print a hello message */ 
  public static void main(String[] args) { 
    BufferedReader in = 
        new BufferedReader(new InputStreamReader(System.in)); 
    String name = "Instructor"; 
    System.out.print("Give your name: "); 
    try {name = in.readLine();}
        catch(Exception e) {
           System.out.println("Caught an exception!"); 
        }
    System.out.println("Hello " + name + "!"); 
  }
}