And how is it used together in game design and development 

Programming is generally - creating a standalone software application for a specific purpose. Scripting is when the software requires an extension of some kind which can be used to run automation and other functions that are peripheral to the software. Scripting is usually interpreted while programming is compiled.

In game design, the scripting part of the logic is done to extend internal functions and components of the code. We require when some kind of customization of the software is needed. In cases where this is not required, we can use programming or rather termed as "hardcoding" of the source.

I hope this answers your question.