REST + MongoDB + HATEOAS?

REST?

Recently I had an interesting experience while implementing HATEOAS to a REST web service, and I was also lucky enough to get to try out a NoSQL database named MongoDB, which I found really convenient for a lot of different cases where you don't need to manage transactions. So, today, I'm going to share with you this experience. Maybe some of you are going to learn something new maybe not, but still, you'll get a refresher on what you already know.

So, first of all, we're going to introduce REST, and slowly we'll get to HATEOAS and MongoDB. So, what is exactly REST?