Perhaps not technically home repair but my car is like an extension of
my home...

Anyway, I noticed that there is a lot of "crud" (grainy white/green
stuff - looks like dried toothpaste) on the positive (red) terminal of
my car battery.

Car otherwise works & looks fine.

Question:
- Is it important to clean the crud off?
- What is the best & also easiest/fastest way to do it?

Thanks