INTRODUCTION TO JAVA
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.

Java applications are typically compiled to bytecode (class file) that can run on any Java virtual machine (JVM) regardless of computer architecture.
Java is, as of 2012, one of the most popular programming languages in use, particularly for client-server web applications, with a reported 10 million users. The language derives much of its syntax from C and C++, but it has fewer low-level facilities than either of them.
Java Compiler is software that compiles the Java code into machine code. Machine code is a set of commands that the hardware understands. The Java Compiler is open source and is called as the Java Standard Development Kit (SDK). Currently version 1.7 is available online. The SDK must be available before editing or creating a Java program
Java Runtime Environment (JRE) is the virtual machine over which the java code is executed. This virtual machine executes the java code. The JRE must be provided before executing a Java program.
Java Integrated Development Environment (IDE) is an editor tool complete with Java SDK and JRE and an editing tool that allows a developer to create edit and execute Java programs. Different IDEs are available including Netbeans, Eclipse, Kawa, etc.
To execute Java programs you will need to download the IDE. I follow Netbeans which can be acquired from https://netbeans.org/downloads/. Download the Netbeans with JDK for Windows (32 bit) and install the software. https://netbeans.org/downloads/
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