No, you do not have to use Mongodb with Node.js
Vast majority of beginner nodejs tutorials use mongodb for the database. For simplicity sake, this is fine for beginners. It saves them the hassle of dealing with SQL table relations, so they can just stick any data in and get it out to render it on the page. So, you need to persist some data After learning the basics of building apps with Node.js, you may decide to build an app on your own. The courses and tutorials you learned from taught you Mongodb. It seems like next logical step: ...