What is 'local'?

I might just sound silly, but no one's ever explained to me what a local is. I'm still learning too, so don't judge me too harshly...

It confines a variable to the scope that it was defined within, with functions, loops, etcetera creating new variable scopes. For example, if you were to create a function with a local variable, that local variable wouldn't be accessible outside of the function.

Here's an example of this "in practice":

function Scope()
	local CantTouchMe = "Yep"
end

Scope()
print(CantTouchMe) 

What would the above print, given what I said initially? If you guessed "Yep", then you're wrong. It would actually print nil.