Practice Linux without installation?

Is there a way to practice in a Linux bash without installing Linux on the notebook?

Have a DVD from which I can start Ubuntu without having to install Ubuntu. It's basically Linux.

Can you download and then burn.

Clear,

a Linux Live CD / DVD or USB stick

Knoppix would be e.g. A live system without installation.

There are Linux live systems on e.g. Disc or USB stick. You could use one to boot a Linux distribution.

You could also install a Linux distribution in a VM (

https://de.wikipedia.org/..._Maschine) and then practice it.