What is that white powder NBA stars rub on their hands before games?

LeBron James and Kevin Garnett do it all the time before tipoff. Is that like some special powder to get a good grip on the ball or something?What is that white powder NBA stars rub on their hands before games?
it's chalk gymnastics people use it tooWhat is that white powder NBA stars rub on their hands before games?
It's talc like stuff that keeps your hands dry. Back in the day it was called ';resin.'; Like the stuff that's in a resin bag on a pitcher's mound.
I would like to say it's Razen powder, the samething pitchers use in baseball and bowlers use to keep their hands dry.
It's chalk. Just like gymnasts use. It helps with keeping sweat off their hands so they can control the ball better.
Donuts powder..lol
its just chalk
chalk...it helps against sweat. its the same thing gymnasts use at the olympics