Java is an object-oriented programming language used to create applications that are compatible with being distributed throughout a network or the Internet.
A Java Applet is a small program that can be returned to a user via a web browser. These client driven mini-programs were designed with the ability to perform simple functions, without having to initiate a subsequent request to the serverserver.
A jpeg file is a common, compressed graphic format that is easily viewed on the Internet. .jpg is the file extension for the file type Jpeg.