ALS - Amyotrophic lateral sclerosis

1. Amyotrophic comes from the Greek word amyotrophia: a- means "no", myo refers to "muscle", and trophia means "nourishment"; amyotrophia therefore means "no muscle nourishment," which describes the characteristic atrophy of the sufferer's disused muscle tissue. Lateral identifies the areas in a person's spinal cord where portions of the nerve cells that are affected are located. As this area degenerates it leads to scarring or hardening ("sclerosis") in the region.
2. Also referred to as motor neurone disease (MND), Charcot disease and
   in the United States, Lou Gehrig's disease.
3. ALS is a neurodegenerative disease characterised by muscle spasticity, rapidly progressive weakness due to muscle atrophy, and difficulty in speaking (dysarthria), swallowing (dysphagia), and breathing (dyspnea) or in simple terms --- The disease affects the brain and the spinal cord causing motor neurones to degenerate and die, leading to gradual paralysis and eventually death.
4. ALS is the most common of the five motor neuron diseases and is a debilitating disease that basically triggers a slow paralysis on those who are stricken by causing the nerve cells to stop working. It's literally an ongoing death sentence. With the exception of some cases like that of Stephen Hawking, most people who are diagnosed with the ailment willonly live only two to five years.
5. There's no cure for the disease as of the moment. The goal of the several groups affiliated with ALS Association is to raise money for research and patient services while at the same time raising awareness.
6. Median survival time from onset to death is 39 months, and only 4% survive longer than 10 years, although rare cases survive 50 years or more. Most die from respiratory failure, usually within three to five years from onset of symptoms.
7. The cause of ALS is not yet completely known. But scientific researches have found that ALS may have some genetic links.
8. The Ice Bucket Challenge, sometimes called the ALS Ice Bucket Challenge which went viral throughout social media during July-August 2014, is an activity involving dumping a bucket of ice water on someone's head to promote awareness of the disease amyotrophic lateral sclerosis (ALS) and encourage donations to research.
9. The rules of the ALS Challenge are simple: those who have been mentioned or tagged by participants have two options to complete the said challenge. The first is to record a video of themselves pouring a bucket of ice-cold water over their head. Those who are challenged but choose not to accept it will have to donate $100 to an ALS association of his or her choice. However, most of those who accepted the challenge, particularly big personalities, still pledged to donate.
10. The idea of dousing cold water on one's head to raise money has early origins, and they are not exclusive to ALS awareness. The exact date of its origin is unclear. A Slate report says that a search of the hashtag #icebucketchallenge on Instagram indicates that video challenges began as early as 2013, with most of them being done just for fun. But the ALS reference in ice bucket challenge videos reportedly began in a video posted on July 15, 2014 by golfer Chris Kennedy. He tagged and challenged his cousin in New York, whose husband has had ALS for 11 years.
11. Its virality on social media did result to the massive increase of support poured in to ALS charities. New York Times reported that the association had received $41.8 million in donations from July 29 until Aug. 21.
12. The feeling of ice-cold water over the body is said to be similar to the numbing effect of ALS.

References:

Amyotrophic lateral sclerosis
FAST FACTS: ALS and the ice bucket challenge
Ice Bucket Challenge Rules Explained: How It Help ALS Charities?
The 'Ice Bucket Challenge' Has Raised $88.5 Million (And Counting) For ALS. Now What?
Ice Bucket Challenge