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Does anyone know how the Brackeys (new) forum was made? I really like it.
HTML and CSS to build the pages and style them to make them look nice.
NodeJS runs on a server and lets the users view the different pages and fills them with information from a database.
For the database you'd probably want MySQL, this also runs on the sever so your NodeJS backend can get all the information it needs.
There's other things to consider as well, frameworks to make creating the website better (e.g. React, AngularJS, etc). But honestly, you're better off making something much more simple first. Forums and stuff are pretty complicated to build - especially alone. So you want to take baby steps.
press ctrl + shift + i
to know better how this I forum was made...^_^