Q) What is here CSS and JS for?

Question

this is the question for the app clearance of thought

Answer 1

Not sure if I understood correctly, but...

CSS = cascading style sheets. It is used for the presentation of your webpages. It helps to keep the styling separate from the HTML. As well, CSS has MANY amazing features to it that is well worth knowing CSS.

JS = Javascript. You can use this to create client-side apps and effects. I recommend learning this inside and out, and then learn something like jQuery or AngularJS that expands upon JS and makes it easier to use.