Okay kiddo, imagine that you have a bunch of toys and you want to play with them all at the same time. But your hands can only do one thing at a time, right? That's a bit like how computers work - they can only do one thing at a time.
Now imagine that you have a robot helper who can hold and play with all of your toys for you, and then show you what each one is doing on a screen. That's kind of like what Terminal Services does for computers.
It's a special software that lets lots of people use the same computer at the same time - even if they are in different places. It's like having lots of robot helpers who can share the computer and do different things with it.
So instead of each person needing their own computer, they can just use Terminal Services to connect to one big computer and share its resources. It's kind of like having a big toy box and all the kids can play with the toys inside without having to have their own toy box.
That's the basic idea of Terminal Services - it helps lots of people share one computer and do different things with it, all at the same time.