What's mAh mean with batteries?

I want to get a few 7.2v batteries for my remote control car. Some range from 1000mAh to 5000mAh. I currently have 2200mAh. Would I have a longer time driving it with a higher mAh? What's it mean and how does it work? Would a higher mAh ruin my car as well? My cars: Tyco Super Fast Traxx. Just fixed it today... show more I want to get a few 7.2v batteries for my remote control car. Some range from 1000mAh to 5000mAh. I currently have 2200mAh. Would I have a longer time driving it with a higher mAh? What's it mean and how does it work? Would a higher mAh ruin my car as well?

My cars:
Tyco Super Fast Traxx. Just fixed it today and excited as **** that it works after so many years.
Radio Shack Samurai
Radio Shack Tempest

All three take 7.2v batteries.

I currently bought the last two. I'd also like to know if I could consecutively use any of those cars with different batteries; if it'd effect it at all and if it'd effect the batteries.

It's a lot to answer but if you know these answers, thanks.
6 answers 6