In this picture provided by the U.S. Army, Army Col. Viet Luong, 3rd Brigade Combat Team, 101st Airborne Division commander, from Clarksville, Tenn., serves Christmas food to soldiers and airmen with 1st Battalion, 187th Infantry Regiment in Bak, Afghanistan in Khost province on Saturday, Dec. 25, 2010. (AP Photo/U.S. Army, Pfc. Chris McKenna)
A photo gallery of Christmas around the world.