As in all aspects of modern life, personal computers have had a profound impact on wargaming. Computers allow gamers separated by many miles to play a game. They also handle many of the tedious aspects of wargaming, such as highly technical rules and record keeping. Finally, with the development of artificial intelligence, computers can actually serve as opponents, and thus provide opportunities for solitaire gaming.
In the video game industry, “wargames” are considered a subgenre of strategy game that emphasizes strategic or tactical warfare on a map. These wargames generally take one of four archetypal forms, depending on whether the game is turn-based or real-time and whether the game’s focus is upon military strategy or tactics.
Many contemporary computer strategy games can be considered wargames, in the sense that they are a simulation of warfare on some level. The mechanics and language have little in common with board and miniature games, but the general subject matter is popular. That said, most war-themed computer and video games are generally not considered wargames by the wargaming hobby. This usually occurs because of if there is a perception that slavish attention to ‘realism’ it will cause a game to be rejected as ‘uninteresting’ or boring so the mass-market video games tend to be easier to get into, and quick to play.
On the other hand, many ‘unrealistic’ video games do include fog of war, meaning that what is visible on the map is limited to what is within a certain range of the player’s units. This is a feature often talked about in traditional wargames, but traditionally impractical to implement outside of a computer. And not all games are equally ‘unrealistic’. For example, the Total War games are a successful RTS series that is historically based, and the Hearts of Iron game series looks at World War II-era politics.
Source Wikipedia: http://en.wikipedia.org/wiki/Wargaming#Computer_versions