xz XZ is a compressed file format. It incorporates the LZMA compression algorithms. The format can only hold one file at a time. This compression format is used by programs like 7-zip and p7zip. XZ format's implementation is freely available.
jar A .jar extension file is a Java Archive format file that is used to store a large number of files into one single file. The basic advantages of .jar extension files are data compression, archiving, decompression, unpacking of the archived file and electronic signing which is one of the advanced features of this format. The Java Development Kit (JDK) contains the Java Archive Tool that is used to perform the basic tasks on .jar extension files. The JAR format is similar to a ZIP file format and it was specifically developed to help download Java applets and its components that include class files, images and sounds in one single HTTP transaction.