The PlayStation (officially abbreviated as PS and unofficially, but more commonly known as PSX or PS1) is a video game console developed and marketed by Sony Computer Entertainment. The console was released in Japan on December 3, , and was released in North America and Europe in September 1995. The PlayStation is the first of the PlayStation series of consoles and handheld game devices. As part of the fifth generation of gaming, it primarily competed with the Nintendo 64 and the Sega Saturn. In 2000, a re-designed "slim" version called the PSone was released, replacing the original grey console and named appropriately to avoid confusion with its successor, the PlayStation 2. The PlayStation is the first "computer entertainment platform" to ship 100 million units, which it had reached 9 years and 6 months after its initial launch. Reactions to the console upon launch were favourable; critics praised the console for the quality of its 3-dimensional graphics. Then Microsoft chairman, Bill Gates, preferred Sony's console to the competition from Sega's Saturn, saying "our game designer likes the Sony machine". The successor to the PlayStation is the PlayStation 2, which is backwards compatible with its predecessor in that it can play almost every PlayStation game. The last PSone units were sold in winter of 2004 before it was finally discontinued, for a total of 102 million units shipped since its launch 10 years earlier. Games for the PlayStation continued to sell until Sony ceased production of PlayStation games on March 31, 2006 – over 11 years after it had been released, and less than a year before the debut of the PlayStation 3.