jar is: Jar (Java Archive) is a file format that is used for aggregating Java files. It can be opened by Winzip.
JAVA is programming language of computer. Jar is a kind of compression method for Java files. It can be opened with Winzip. Jar was specially created for running Java class files.
If this file is being used for a web page, essential codes can be worked by installing Java virtual machine.
Jar File format viewers or openers
winzip, java virtual machine
Jar File related links.