.Jar means how it is different from .java

Answer 1

JAR file is the compressed file format. You can store many files in a JAR file. JAR stands for the Java Archive. This file format is used to distribute a set of java classes. This file helps you to reduce the file size and collect many file in one by compressing files

Answer 2

The .java is the source before compiling it to the .class file. In Eclipse you create a new class, enter your code and that code is saved as a .java file.
The .jar as stated below by Raj Joshi

Answer 3

yes raj is right