What is Java?

Java is one of the most popular languages in programming world. James Gosling developed Java in 1995. It’s previous names are Greentalk, Oak etc.

• Object oriented language
• Class-based language
• Concurrent language
• Secured language
• General purpose language
• High level language
• Robust language
• Dynamic language
• Software platform

Application

• Computer Applications
• Web Applications
• Enterprise Applications
• Mobile Applicationa
• Games
• Robotics
• Smart Card
• Embedded System

Java Platforms

• Java standard Edition
• Java Enterprise Edition
• Java Micro Edition
• JavaFX

Java Virtual Machine (JVM)

JVM provides a runtime environment in which Java bytecode can be excuted.

Java Runtime Environment (JRE)

JRE is implement of JVM. It contains a set of libraries and other files which uses at runtime.

Java Development Kit (JDK)

JDK is sofware development environment which is used to develop java applets and apps. It contains JRE and other development tools.

Java Hello_world code

\\ my first java program
public class Hello_World{
       public static void main(String[] args){
      System.out.println("Hello World!");
    }
}