Learn Java - Java tutorials for beginners
Java is one of the most popular computer programming language in computing world. If you are planning to learn only one programming language and looking for a job, Java is your best bet at this moment.
Java is a general purpose programming language and is class based object oriented language with support of multi-threading / concurrency built in the language itself. Java's core philosophy is 'write once, run anywhere' has made it widely successful.
Sun Microsystems released the first version of Java programming language in 1995. It has been more than 20 years since and Java is still one of the most versatile language around. Java has been used extensively over last 15 years - right from enterprise applications to web backends to large scale data processing. More recently, Java has gained another boost due to popularity of Smartphones as Java is the primary programming language for Android (the dominant OS for smartphones).
Currently Oracle is the official owner and maintainer of Java language. Though for all practical purposes, everyone is free to use Java language and its associated compiler and Java virtual machine (JVM) without any charges.