What is the purpose of Manifest file

Question

http://java.sun.com/developer/Books/javaprogramming/JAR/basics/manifest.html

What does a manifest file do? What is the purpose of it?

Manifest-Version: 1         


        

Answer 1

The manifest is a specific no-class file assembled within a Jar, which contains the descriptive pairs of keys and values of this Jar and we usually called it metadata, it tells end users or callers:

what the propose of Jar? who is the writer? when it was created? what is creation env? what is JDK version? and even more...(Assuming have these values in manifest)