The Sony PlayStation 2 is the best-selling video game console of all time, with over 100 million units sold worldwide. The PS2 (as it is commonly known) has a broader age-range appeal than its main rivals, the Nintendo GameCube and the Microsoft Xbox. Released in 2000, the PS2 was backwards-compatible with Sony's previous-generation console, the PlayStation, but featured better graphics and more processing speed. Like the Nintendo GameCube (but unlike the Microsoft Xbox), the PS2 lacks a hard drive so users must buy a separate memory card to store their games in progress. Users can play this game either by themselves on their own TV or connected with other players through the internet.