(jar) A compressed archive file coNTaining Javaclass files, filename extension: ".jar". The Java DevelopmeNT Kit coNTains a tool called "jar" for creating .jar files, similar to the standard Unixtar command. As well as archiving and compressing the Java class files, it also inserts a "manifest" file which can coNTain information about the class files, such as a {digital signature}. Combining class files iNTo a single archive file makes it possible to download them in a single HTTP transaction. This, and the compression, speeds up execution of Java programs delivered via the INTernet. (2001}-02-03)