You keep seeing all of your friends under a purple tint, and you're not sure why?  Well, it's World Cancer Day, February 4, 2014.  And, in honor of this special day, Chevrolet has vowed to donate $1 to the American Cancer Society for every person who changes their profile pic to purple!

Click here to check out Chevy's World Cancer Day event!

Go to this website and follow the easy instructions, and you too can have a purple pic to show your support! #PurpleYourProfile

See...