the new DVD format and with capabilities of playing back DVD movie disks and CD audio disks, as well as playing PlayStation games in a backward compatible mode alongside PS2 games. Nintendo followed the Nintendo 64 with the GameCube in 2001, its first console to use optical discs, though specially formatted for the system. However, a new player entered the console picture at this point, Microsoft with its first Xbox console, also released in 2001. Microsoft had feared that Sony's PS2 would become a central point of electronic entertainment in the living room and squeeze out the PC in the home, and after having recently developing the DirectX set of libraries to standardize game hardware interfaces for Windows-based computers, used this same approach to create the Xbox. The PS2 remained the leading platform for the first part of the decade, and remains the best-selling home console of all time with over 155 million units sold. This was in part to a number of critical games released on the system, including Grand Theft Auto III, Metal Gear Solid 2: Sons of Liberty, and Final Fantasy X. The Xbox was able to gain second-place to the PS2 sales, but at a significant lost to Microsoft. However, to Microsoft, the loss was acceptable, as it proved to them they could compete in the console space. The Xbox also introduced Microsoft's flagship title, Halo: Combat Evolved, which relied on the Xbox's built-in Ethernet functionality to support online gameplay. By the mid-2000s, only Sony, Nintendo, and Microsoft were considered major players in the console hardware space. All three introduced their next generation of hardware between 2005 and 2006, starting with Microsoft's Xbox 360 in 2005 and Sony's PlayStation 3 (PS3) in 2006, followed by Nintendo's Wii later that year. The Xbox 360 and PS3 showed a convergence with personal computer hardware: both consoles shipped with support for high-definition graphics, higher-density optical media like Blu-rays, internal hard drives for storage of games, and had built-in Internet connectivity. Microsoft and Sony also had developed online digital services, Xbox Live and PlayStation Network that helped players to connect to friends online, matchmake for online games, and purchase new games and content from online stores. In contrast, the Wii was designed as part a new blue ocean strategy by Nintendo after the poor sales of the GameCube. Instead of trying to compete feature for feature with Microsoft and Sony,