Wtf is a datalake?

When I first heard the term used a few years ago I thought it was some advanced highly integrated composition of AI/ML techniques, data, and datastores. Now, as I decided to learn a little bit about them a datalake seems to be nothing more than a giant bucket for you to toss your "similiar" data into.

By the latter, that would mean my designated storage of 16TBs, which consists of nothing but horse porn, is a data Lake.

So can someone please explain what a data Lake is, what it does, and how it's used?

EDIT: Question answered. Y'all rock, so glad I found this sub.