Electronic Wargaming is an electronic version of tabletop wargames, except it is in real time, and is normally made with premade terrain and armies, but it still involves some kind of tactical fighting. Note that first person shooters should not count towards wargaming, because they require hardly any more tactics than hide behind stuff, and shoot nearly anything you see, and you really do not need to make vital choices that affect anyone else on your team (good or bad things). There are hundrdeds of games set in to a few genres.
The first section is fantasy wargaming. These are games like the RTS game series,Warcraft, the Diablo series,or the new Microsoft game, Age of Mythology. These are games that normally have midieval style weaponry with fantasy creatures such as dragons, orcs (orks), elves,etc.
Another type of gaming is the sci-fi, which has games such as Homeworld:Cataclysm, Starcraft, Command and Conquer and, Fallout. Generally these include waeponry of high technology, frightening aleins, spaceships, and other technologically awesome wargear.
One other style is the modern day type, such as Ghost Recon, any Naval Based game, and modern day armies. These games have realistic weapons, some of which are (or have been) in service around today.
The last type are games which are spread over a huge expansion of time, like Empire Earth, where you can practically change the Earth's History.
Electronic wargaming is a very diverse system, where infinite realms can be imagined and played over in real time, without the cumbersome turn-based system table top games usually employ. These systems also help with a bounty of realism, as you see buildings, and troops destroyed, in full color and sound, while on an awesome landscape.
