A viral social media craze that was popularized in the Northern hemisphere summer of 2014. It's exact origins are uncertain, but it first grew to global prominence from the Northern United States.
The challenge dares the nominated participants to pour a bucket of iced water over their head within 24 hours.
Once the participant has completed the challenge, they may call out the names of other people that they wish to challenge.
Some variants of the dare require participants to donate money to charities such as the ALS Association (US) and MND Association (UK), with the donation required dependent on whether the dare was completed.
The viral challenge became a great fundraising success once celebrities began to take part - including Bill Gates, Barack Obama and Oprah Winfrey.
I accept the Ice Bucket Challenge.
*pours iced water on head*
I nominate Stephen Fry, Mr T. and Chuck Norris.