The Ice Bucket Challenge, is an activity involving dumping a bucket of ice water on yours or someone else's head to promote awareness of the disease amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig's Disease) and encourage people to donate. It went viral on social media during July–August 2014. The challenge encourages nominated participants to be filmed having a bucket of ice water poured on their heads and then nominating others to do the same. It is said that nominated participants have 24 hours to do the challenge or must donate $100.