What is WorldRoot and why is it associated with workspace?

What the title says. Stumbled across WorldRoot when I noticed that Raycast() function didn’t exist in the workspace api. Why is it in WorldRoot api and not in workspace and why are functions in WorldRoot called by using workspace?

workspace is locked in game you can’t change anything in workspace while the game is running

Because both WorldModel and WorkSpace classes inherit from WorldRoot superclass so they can use the functions that WorldRoot have and that includes :Raycast() function too.