>but didn't tell me what it actually IS or DOES

It tells you right at the start:

"Easily run Windows software on Linux with Bottles!"

That's all you need to know. If Linux wants to be more mainstream it needs to drop the "Bottles is a wrapper around WINE". What's a wrapper? What's WINE? It doesn't matter. All the user need to know that you can easily run Windows software on Linux with Bottles