Java Features

Platform Independent

Java compilers translate a Java source file (.java) into a Java class file (.class).

A Java class file runs on any platform with a Java Runtime Environment (JRE).

Let's call a Java class file (.class) a bytecode because it is interpreted in bytes by the Java interpreter (java.exe).

Java Runtime Environment (JRE): A JRE is what you need to run a Java program.
A JRE comprises a Java Virtual Machine (JVM) and Java APIs and other files, which help a JVM to run Java bytecode.
Java Development Kit (JDK): A JDK is composed of a JRE and tool programs, which it is necessary to develop Java.

Java is object-oriented programming language.
Java supports basic concepts of object-oriented programming, such as: