To put it as simply as possible, if you think of electricity like water--the amp rating would be comparable to the size of the hose you are running water
through. Higher amp rating means the ability to safely deliver more power. Try to push more water
through a small hose and it will burst--messy, but no biggie...except in the case of pulling too much power from a battery you might just create a meltdown--sometimes catastrophic and/or expensive.