World AIDS Day, observed December 1 each year, is dedicated to raising awareness of the AIDS pandemic caused by the spread of HIV infection. It is common to hold memorials to honor persons who have died from HIV/AIDS on this day. Government and health officials also observe the event, often with speeches or forums on the AIDS topics. Since 1995, the President of the United States has made an official proclamation on World AIDS Day. Governments of other nations have followed suit and issued similar announcements.
–wikipedia

for 2008’s theme is “Stop AIDS. Keep the Promise – Lead – Empower – Deliver” –UNAIDS

Scanning electron micrograph of HIV-1, colored green, budding from a cultured lymphocyte.
What is AIDS? Acquired Immune Deficiency Syndrome or acquired immunodeficiency syndrome (AIDS) is a set of symptoms and infections resulting from the damage to the human immune system caused by the human immunodeficiency virus (HIV). This condition progressively reduces the effectiveness of the immune system and leaves individuals susceptible to opportunistic infections and tumors. HIV is transmitted through direct contact of a mucous membrane or the bloodstream with a bodily fluid containing HIV, such as blood, semen, vaginal fluid, preseminal fluid, and breast milk.This transmission can involve anal, vaginal or oral sex, blood transfusion, contaminated hypodermic needles, exchange between mother and baby during pregnancy, childbirth, or breastfeeding, or other exposure to one of the above bodily fluids.
–wikipedia

read more:
Wikipedia : World AIDS Day
World AIDS Day 2008
World AIDS Day 2008 : What is HIV?
The New Straits Times Online
Malaysian Medical Resources
www.unaids.org