Short for Java archive, a JAR file is a collection of multiple files as one single file. JAR files are an easy way to distribute Java applications, much like compressing a file into a zip file is an easy way to distribute other programs over the Internet. To start a JAR file, type the following command.
java -jar example.jar
To explode or extract the JAR file, type the following command.
jar -xf example.jar
If you are familiar with Linux or Unix, you can think of a JAR as similar to a tar archive.