Vacant

Vacant is a small map that is based in an abandoned office. Shotguns and SMGs are generally favoured, but LMGs and Assault rifles can prove useful in the outdoor sections of the map. Though the map is roughly half indoors and half outdoors, almost all of the combat occurs indoors. Because of this, helicopters are nearly pointless on this level. However, due to holes in the ceiling of the warehouse on the left-most side, and the small open area in the center, a well placed air strike can easily kill unsuspecting members of the other team. Be very careful when running through the hallways. Usually the hallways are literally exploding with all the grenades being dropped from martyrdom and thrown grenades. Also this map is very useful for getting the multi-RPG challenge, multi grenade challenge, and pretty much any other challenge having to do with explosives and a lot of people because of the closeness of the hallways. Woodland or digital camouflage is often preferred.

Trivia

 * This map, and Shipment, are thought to be located close to Prypiat, Ukraine, where the Chernobyl Nuclear Power station's workers lived. This is because the 1980s style Ukrainian tower blocks can be seen in the distance. This is strange, because flat screen computer screens can be seen in the office. This is most likely an oversight or simply done for the sake of convenience so the developers wouldn't have to take the time to develop a whole new set of models for 1980s-era office equipment. Funnily enough, both maps state they are in Russia, in the map description.
 * The portion of the office that features the cubicles bears an uncanny resemblance to the starting building in the Call of Duty 2 singleplayer mission Demolition.
 * When the player spectates outside the map and look at the sides of the buildings outside, there are weird and kind of disturbing graffiti paintings of cartoon characters. They look a bit like the cartoon band Gorillaz.
 * There is a poster on a wall in one of the rooms depicting a World War II-era female Russian soldier that is strangely wielding an American Thompson, which the Russians never used. This picture may also be seen in the MW2 single-player map, Loose Ends.
 * There is a Truck parked outside of the warehouse with a license plate "R3TARD0"
 * An Intel laptop can be found in the office area.
 * If you stand still long enough in the office area you will hear a fan clicking, someone talking somewhere on the map, and footsteps. This is all heard above the action music.
 * Vacant is rumored to appear in the 2nd map pack for Call of Duty: Modern Warfare 2.
 * The apartment buildings around the right side of the building (outside the map) don't have any collission efffects. If a chopper is called in, it is not uncommon for it to go near these apartment buildings and for at least part of it to phase through them.

Ghost Rumors
There have been multiple rumors concerning what is called the "Ghost of Vacant", which is assumed to take the form of a random player and walks in the form of a zombie. The zombie is indestructible and seems to skip around the map. This is however fake as in the YouTube video that depicts it the clock skips and there is a well known glitch to get the characters to skip around the map.