JavaScript libraries are a collection of pre-written JavaScript programs which have a defined Application Programming Interface (API)1 that can be used by other programs to make use of their functionality. For instance, a library might provide a collection of useful objects such as tables and graphs of different kinds. Those objects would have parameters defined so that you could provide data to them and define things about the layout of the objects.
If you have used SAS/AF in the past, you will see similarities between JavaScript libraries and SAS/AF. Both allow you to interact with a client by building ...