Some executables are special. When you run them, they automagically run as root instead! But if sudo isn’t very, very careful, you can trick it into letting you run things as root that you shouldn’t be able to.

Run0 DM’s systemd asking it to go fork a process as root for you, and serves as the middleman between you and the other process.

You had me rolling, bud.

(I’ll attempt this based on my understanding of both)

Pouring a cup of juice is something an adult needs to be involved with.

sudo is when you ask for permission to pour your own cup of juice. You ask an adult, they give you the cup and the juice, and then you’re responsible for pouring it. If the adult isn’t paying attention they may leave the fridge open for you to go back for more juice or another beverage, but otherwise you’re limited to the amount of juice the adult has given you.

run0 is when the adult just gets you a cup of juice. You tell them what you want, they go and pour the juice, and just give you the cup with the juice in it. You never enter the kitchen, so you don’t have access to the fridge, just your cup of juice.