Facebook enabled members to while Twitter allowed people to change the colour of their tweets by entering #red along with the text.
According to (Red) its Facebook fan membership doubled in size to around 380,000 as a result of the day's activity. Additionally 60,000 members added red to their profiles and 25,000 shared a (Red) promotional video.
On Twitter 500,000 people added the hashtag #red to their messages including Barack Obama and celebrities such as Ashton Kutcher, Davina McCall and Paris Hilton.
Google.com featured a World Aids Day ribbon, linking through to various charities connected with fighting the disease.
Additionally Nike tied in with (Red) to launch a brand of red football laces. All the profits from the product will be donated to the charity.