The PS2 can read CDs, for playing audio CDs and original PlayStation games, and DVDs for DVD Video and PS2 games. Its ability to play DVD movies was an important selling point at a time when few people owned a separate DVD player.
When it was released, the PS2 had many advanced features that were not present in other contemporary video game consoles, including its DVD capabilities and USB and IEEE 1394 expansion ports. It was not until late 2001 that the Microsoft XBox became the second console with DVD support, although playing DVD-Video titles on XBox requires the purchase of an additional module (containing decoder software and a remote control). Most reviews claim the PS2's DVD support to be mediocre at best.
Support for original PlayStation games was also an important selling point for the PS2, letting owners of an older system upgrade to the PlayStation 2 and keep their old software, and giving new users access to older games until software was developed for the new system.
Software for all PlayStation consoles contains one of three region codes, for Japan, the Americas, or Europe. Discs also deviate slightly from the CD-ROM and DVD-ROM standards in ways that make it impossible for the average consumer to duplicate discs or create her own software for the system. However, Sony has released a version of the Linux operating system for the PS2 in some regions in a package that also includes a keyboard and hard disk drive.