Java was designed by Sun Microsystems in the early 1990s to solve the problem of connecting many household machines together. In 1991 java was started initially it was called as “Oak”. Later Java became popular for developing web internet applications. Java was developed by James Gosling and a small team of engineers. James Gosling is considered as “FATHER OF JAVA”. The main concept of java is “Write Once, Run Anywhere”. Java first publication 1.0 was released in 1995 by Sun Microsystems. Now, Sun Microsystem is the part of Oracle Corp.