The Ice Bucket Challenge brought awareness to ALS in 2014. It's back a decade later with a new cause. Here's why, where to donate and the rules.

The Ice Bucket Challenge is back. The challenge that splashed through social media in 2014 as people all over the world dumped buckets of ice water on their head to raise money and awareness for ALS ( Amyotrophic lateral sclerosis) research is returning, but this time for a new cause.