Colin McRae: Dirt 2 (Dirt 2 in North America) is a racing video game developed and published by Codemasters for PlayStation 3, PlayStation Portable, Wii, Xbox 360, Nintendo DS, Microsoft Windows and OS X.

• Colin McRae: Dirt 2 features five racing disciplines, all of which are playable offline (against AI bots when applicable) and online. In addition, three “special modes” are included. Colin McRae: Dirt 2 runs on an updated version of the EGO engine, which powered Codemasters’ Race Driver: Grid as well. The engine features, most notably, an updated physics engine, which models realistic weight transfer during turning maneuvers, allowing the player to incorporate advanced driving techniques, such as the Scandinavian flick.
• Rally racing occurs on non-circuit roads which usually involve public (closed) routes and technically challenging courses. Usually involving staggered starts, each driver competes against the clock. In addition, during rally events, a co-driver is present, constantly reading pacenotes to guide the driver along narrow and meandering tracks of up to 6 km in length.
• Rallycross races involve cars identical to those used in rally events; the races themselves, however, are very different. Each rally-cross race involves up to eight racers competing in multiple lap events on circuit tracks of mixed surface type. The tracks, half tarmac and half dirt, exist in closed settings, such as in or around stadiums, and are approximately 1 to 1.5 km in length.
• The most similar real-world equivalent of Trailblazer events are hill climbs. Unlike hill climb events, however, trailblazer races do not require a positive change in elevation. Similar to rallying, trailblazing features staggered starts. Trailblazer (and hill climb) cars, unlike rally cars, usually feature massive aerodynamic aids, such as spoilers, diffusers, and splitters to help keep traction at higher speeds, regardless of track surface or conditions.
• Raid races are multi-car events involving heavyweight vehicles, such as buggies and trophy trucks. Each race begins with a simultaneous start of up to eight competitors, with tracks averaging 5 km in length. Landrush events are similar to raid races, but take place on a circuit. Each event features eight racers on a dirt track of about 1 km, and involve multiple laps.

Source: Wikipedia

Dirt 2 System Requirements

Minimum:

• OS:Microsoft Windows XP, Vista or Windows 7
• Processor:Intel Pentium 4 3.0Ghz, AMD Athlon 64 3400+
• Memory: 1GB (2Gb for Windows Vista)
• Graphics: ATI Radeon X1500, NVIDIA GeForce 6800
• Storage: 10 GB

Recommemded:

• OS:Microsoft Windows XP, Vista or Windows 7
• Processor:Intel Core i7 or AMD Phenom II
• Memory: 3 GB
• Graphics: ATi Radeon HD 5700 Series
• Storage: 10 GB