It’s the group which created standards for JPEG images (It is the type of file, and JPG is its file extension). JPEGs utilize adjustable compression, which means you can reduce their size (this can be at the cost of clarity) when you need to post them on the web.
The scripting language which allows web designers to create various interactions on web pages. Historically this script was used in the process of form validation; however, it is now used for adding special visual effects. It also offers the ability to load the new content without actually having to reload the entire page.