This format is a Java archive and is presented as a typical ZIP file, in which part of the program is written in Java language. It was gradually replaced by new mobile platforms, since JAR is used for launching applications and games on early generation mobile phones. They can contain a digital signature, and they’re actively used in popular browsers for storing supplements.
A common format for compressing data. It’s used by a large number of applications for the exchange of data, back-ups and file compression. In ZIP archives they use various compression algorithms. The cryptographic algorithm is proprietary, so confidential data is better stored in an archive with a more complex protection system (RAR, 7z, etc.).