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Team Deathmatch
Use teamwork to kill enemy players and reach the score limit.
Team Deathmatch can be played online with up to 18 players at a time in a team-versus-team battle. There are no objectives in this mode, aside acquiring more points than the other team. This mode is respawn-based, which means you need to kill as many opponents as you can to get the most points for your team.
Free-For-All
No Teams, everyone for himself. Kill everyone.
Free for All is just what it sounds like: kill anything that moves. Again, this is a respawn-based mode, and you have a predetermined amount of time to rack up as many kills as possible and land at the top of the list.
Domination
Three flags need to be captured and held for as long as possible. Hold the designated positions to gain points.
Domination mode features three flags that you can capture to rack up points for your team. A captured flag continuously generates points for your team. Multiple captured flags generate more points for your team until the enemy captures them back. Either team can capture a flag, and you can recapture flags at any time. The more teammates you have in the vicinity of a flag, the faster you can capture it. The team with the most points when the rounds ends wins the match. Domination is a respawn-based type of combat.
Ground War
Rotating game modes (Team Deathmatch, Domination, ...) with a 18 player limit (on consoles) in stead of 12.
Search and Destroy
S&D is not respawn-based, so you must be a little more careful when you jump into such matches. This mode is objective based. One team begins with a bomb and must drop it at either of two plant locations. you can also eliminate the entire enemy contingent to win. Teamwork is crucial for winning in this mode, so cooperate with everyone to clear a path to a drop spot, get the bomb planted, and secure the area before the enemy can defuse it. If you plant the bomb and the enemy defuses it before it explodes, the enemy wins that round.
Headquarters Pro
Capture the headquarters and defend it from the enemy.
Headquarters is a respawn mode in which your team must capture HQ points before the enemy team can. Once the game randomly selects a headquarters point, you and your team must get to it as quickly as possible and gain control of it. Take control of an HQ by standing in its vicinity until the progress bar appears. A filled bar signifies that you successfully taken control of the HQ point. Now you must defend it. Once you secure an HQ, your team can no longer respawn. After the enemy destroys the HQ, your team regains the ability to respawn. The PRO addition means that when the HQ has been randomly selected by the game, it will not be online (to capture) right away. Instead, both teams have time to get from one side of the map to the HQ before it comes online.
Demolition
Defend and destroy both objectives.
Demolition mode is very similar to S&D, with the exception that you must plant a bomb at both spots to win, instead of just choosing one drop location. This is a respawn-based game mode.
Capture the Flag
Capture the enemies flag and return it to your teams base to score points.
Capture the Flag is a respawn-based mode that features one flag at each team's base. Each team must grab the other team's flag and bring it back to their base to scare points. Someone almost always guards the enemy flag, so avoid rushing in and trying to grab the flag without teammate assistance.
Sabotage
1 Bomb in the center of the map. Grab it and destroy the enemy objective.
Sabotage is kind of a combination of S&D and Capture the Flag. Each team tries to acquire a centrally located bomb and plant it at the enemy base. The more times you plant the bomb, the more points your team gets. Don't forget that everyone can see a big "kill" arrow over our head when you pick up the bomb. If you defuse a planted bomb, it reappears, giving both teams the chance to plant it again at their enemy base.
Mosh Pit
Mosh Pit is a game mode that has been added to the playlist well after the game was released. It's a mix of all game modes, with the exception of 3rd Person Cage Match and Team Tactical.
Core (a.k.a. Normal First Person)
This type of play has the most playlists enabled (all of the above modes). You have normal health (100%) which fully generates in 5 seconds after you've been hurt. You have a HUD (Heads-Up Display) enabled which tells you valuable information about many things. You will see a radar/map in the top left corner that shows the map layout, friendlies and enemies that shoot without silencers. You can also see how many bullets you have left, both in your weapon and how many in spare magazines. You also see what equipment you have left to use.
Hardcore
Hardcore settings remove your HUD (Heads-Up Display), decrease your health (30%), and eliminate your health regeneration abilities. All of the onscreen intel disappears. You have no crosshairs except what you attach to your weapons, such as scopes. You don't get a timer or clock, and you can't see how many points your team has or how much ammo you have left. The radar/map is disabled by default until you or any one of your team calls in a UAV killstreak. You don't get any indicators, such as a grenade landing near you, and you don't get any text prompts for things like planting a bomb. On top of all those challenges, Hardcore modes usually require only a bullet or two to kill someone. On top of that, friendly fire is enabled so you will kill a friendly when shooting at him. All of these features make the game feel more realistic. You don't empty entire mags into people in Hardcore, and that encourages somewhat more cautious play.
3rd Person
Third person is new in Modern Warfare 2. It is much like "Core" but with this type of play you don't play through the eyes of your character. This time around you will fight in third person, with the camera hovering behind your character.
