If you know what a virtual machine is, a docker container is like a virtual machine that has a curated environment for running a specific program.

To get more technical, they are distinct from VMs in that they share the host machine’s kernel, so they are not as isolated as a VM. Docker (the program used to build or deploy Docker containers) has an internal network it manages, mostly automatically, which contributes to the ease of deploying containers and having the curated environment that makes containers work out of the box on whatever host they’re deployed.

So let’s say you wanted to run a Wordle clone website. You could find a “docker-compose” file online, change the configuration parameters to your liking, tell Docker to boot it, and the application and all its dependencies will be downloaded and built into a ready-made server with Wordle, the same as it works on every other machine with Docker.