The devastating earthquake in Haiti is the biggest natural disaster so far in the Twitter era, and response on the micro-blogging site has been accordingly momentous.
According to Twitter.com, four of the 10 most popular topics posted on the site were related to Haiti, where the death toll from a magnitude 7.0 earthquake that struck on Tuesday could run into the tens of thousands.
Among them were the terms Port-au-Prince, Help Haiti, and Yele, a charity organization founded by Haitian-born musician and record producer Wyclef Jean.
Jean was asking people to text the word Yele to the number 501501, which will charge the user $5 and donate the funds to the Yele Haiti Earthquake Fund.
WARRIORS HAITI NEEDS U NOW! Jean tweeted on Wednesday, about 24 hours after the quake. PLEASE LEND YOUR PRAYERS AND SUPPORT TO THE EARTHQUAKE RELIEF EFFORT TEXT 'YELE' TO 501 501 OR VISIT YELE.ORG.
Since its creation in 2006, privately owned San Francisco-based Twitter has become wildly popular as a social networking site and means of communicating information in 140-character bursts.
A search for the term Haiti on Twitter found it awash with other means to help, in several languages, including links to websites for such agencies as the Red Cross and Unicef.
Twitterers also shared news from the region, such as aftershocks rattling the Haitian capital, Port-au-Prince, or the rising death toll. Some sought information about missing or injured friends and relatives.
Others took to the website to pour out their shock, grief or anger. A user with the screen name Crys_Michelle said: R.I.P. to all involved with the Haiti disaster!!! Ssooo sad.
A user named ladybot wrote: Reading about Haiti on CNN.com; started crying. It sounds like absolute hell on earth. Not feeling like my $$ are nearly enough.
Many reacted to U.S. televangelist Pat Robertson, who told viewers of his Christian Broadcasting Network on Wednesday that Haiti had been cursed by a pact to the devil in 1804 -- a reference to the date of its independence from France.
User michaelianblack wrote, What kind of deal with the devil did we make to deserve Pat Robertson?
Facebook spokesman Larry Yu said that since the quake, there had been over 1,500 status updates a minute containing the word Haiti.
(Editing by Ed Stoddard and Peter Cooney)