Aggregators such as TweetDeck collect and organize tweets, making them easier to search for the latest news or pictures. One, TwitterMap.tv, shows where people are tweeting geographically so users can watch others' tweets pop up from every corner of the globe.
One girl near Jakarta, Indonesia, echoed the simple message of thousands of others: "My heart goes out to all the victims."
A Facebook group dedicated to the victims of the earthquake already has more than 29,000 members and is quickly growing.
"Haiti is on my mind," user Joy Montgomery wrote. "[I] can't stop thinking about all those people trapped in rubble. I just kissed my kids, and I am feeling so grateful for my comfortable life."
While social networking is by nature a grassroots method of communication, official sources have also taken advantage.
The White House Twitter feed urged its followers to donate to the Red Cross for relief through text message, and the Department of State used its blog, DipNote, to encourage donations as well.
As relief agencies around the world scramble to help those in need, most people are left sending their best wishes in whatever form they can.
"We pray none affected shall faint, but be strong and courageous," one user said recently. "We're with you."