Also known as ALS Ice Bucket Challenge, it's the latest pop culture phenomenon in US.

It involves people dumping a bucket of ice or freezing cold water on someone's head to raise charity for ALS Association and then after he/she has already done that, he/she is able to challenge 3 people to dump a bucket of ice on their head.

The trend started in America where people wanted to raise awareness of Amyotrophic lateral sclerosis (ALS) – also referred to as motor neurone disease.

Many celebrities, politicians, athletes participated in this phenomenon. Popular people like Bill Gates, Mark Zuckerberg,Emmy Rossum, Oprah Winfrey, Ivanka Trump, etc accepted the challenges.

The rules states that Within 24 hours of being challenged, participants are to video record themselves in continuous footage. First, they are to announce their acceptance of the challenge followed by pouring ice into a bucket of water. The bucket is then to be lifted overhead and poured over the participant's head. Then the participant can call out a challenge to up to three other people. There is disagreement about the rules at this point. In one version of the rules, the participant is expected to donate $10 if they have poured the ice water over their head and donate $100 if they have not.