What are the two tabs css and js for?

Answer 1

This Tabs on Sololearn are for the "external". It is better to put Javascript(.js) and CSS (.css) external, so the website can load faster. If you develop in real, you must write the source of the files in the head. But on Sololearn, you can write it inside the CSS and Javascript Tabs.

Answer 2

CSS is to add design or edit presentations of a webpage ... CSS files has a extension ".css" .. Where as JavaScript is to add functional effect or functional contents (ex: addition) .. JavaScript files ends with ".js" extension.. JavaScript can be manually inserted by using <script> tags in html.. Hope it helps .. Please do upvote :)

Answer 3

css is for css design files ".css" and js is for javascript ".js"
javascript is client side scripting btw