When I needed to reinstall an operating system to a computer, I used to have one USB stick per operating system. So with a collection of some Windows, Linux and anti-virus related operating systems I used to occupy several USB sticks.
Now I heard about Ventoy. Ventoy offers a tool that allows you to create a bootable USB stick which can host several operating system installation files (ISO's) on one USB stick.
I now use it, and it works like a charm. The only limit is the amount of space on your USB-stick.
