Docker Hub

Docker Hub is a repository for Docker images, that you can use to deploy into your Docker environment.  There are a bunch!

There are other repositories out there, but a lot of them feed back into the Docker Hub in one way or another.  You could also start developing or turning apps/code/etc into containers and pushing them up to the hub.  Me just saying that should give you an idea of how massive the Docker Hub is.

Explore The Hub
Docker Hub

There are a lot of images, and a lot of them has different ways to get them into your system and functional.  I am not going to get into all of those ways, but I am going to show how a few simple apps (with big functionality) are installed.  

Explore and search through the hub.  There are tons of images that will really get your brain juices flowing.