The radar in this game is often a deciding factor in survival. For most players, the strategy is second nature, but it's surprising how many players don't know how to take advantage of the radar to keep themselves alive. I thought I would take a few paragraphs and offer some of the techniques that can take full advantage of it. This disucssion will focus mainly on Black Ops 2, however the techniques here will likely carry over well to ghost and other past COD games since the radar mechanic doesn't vary all that much between game releases.
In case anybody doesn't know, whenever you fire an usupressed gun or your opponents have a UAV in the air, you appear as an orange dot on the opposing teams minimap. The supressor prevents this when you fire and the ghost perk will prevent you from being on a UAV if you are moving at half speed or greater. The orbital V-stat give the opposing team your real time posission and directon and you cannot avoid being on it through conventional means. UAV's can be shot down and Counter UAV's blind the opposings sides radar completely.
Using the Radar Defensively:
Quite a few players don't understand that the radar is meant to be a defensive tool rather than offensive one. It can be used offensively, but this is much harder than it appears. For most inexperienced players who are out hunting for kills, when they see a little orange dot appear, they immediately travel towards it to get a kill. When players appear on the radar for firing a weapon, they are usually wounded from a gun battle and have a half empty magazine for killing someone. However, when players are in a vulerable state they are more alert and expect other players to come and kill them. Rushing off blindly towards a dot on the map any distance from you is a good way to get yourself killed.
By the time you reach the dot on the map, the other player has recovered any missing health, reloaded and likely moved to a different location. Also, he may have team mates near by and they will be happy to kill you as well. Instead, you should use the knowledge you gain from the radar to gain the upper hand. The position the dot is tells where they fired their weapon. Most likely, they are wounded and need to reload. They are going to try and find a safe place nearby to revcover their health and pop in a fresh mag. If you have good map knowledge, it's not hard to get an educated guess to where they are going to try and do that. You should instead use that knowledge to go and flank that position and try to catch them off guard for an easier kill. Also, if you see multiple dots, it might be wise to avoid a group too large for you to tackle alone without the element of surprise.
The radar can also tell you quite a bit about your opposing team's play style. Having a UAV in the air for 30 seconds reveals a lot. When your team get's it's first UAV find a safe spot and open the whole map for a few seconds. Count the number of dots present on a sweep. This will tell you the number of opposing team members running stealth build. See if there are any clusters. This let you know if they are working in fire teams or running lone wolf style. Watch the dots movements, this will let you know if they are camping, play objectives or just combing the map for kills randomly. A skilled team armed with this information can dominate any game type and it's well worth the 20 to 30 seconds it takes to glean it.
I am going stop here to avoid making this too long to digest. If there is interest in this topic I might add to it later. Also feel free to share any additional tips you have or ask any questions.