What Are the USB Ports on the PlayStation 2 Used For?
The USB ports on the front panel of a PlayStation 2 are used to connect peripheral accessories to the console to enhance its functionality. Just like with a computer, hard drives can be attached to a PlayStation to save game data. They can also be used to connect special controllers, headsets, webcams, and even a keyboard and mouse, which effectively permits converting a non-slim PlayStation 2 into a Linux computer.
Some PlayStation 2 games include USB accessories, such as a buzzer for the game Buzz! and microphones for Singstar and Harmonix Rock Band. Both these accessories come in wired and wireless versions, and both connect to the system via USB. Another popular USB accessory is the EyeToy, which allows players to record videos and take pictures, letting them put their photo in a character model's face. There is also the Dance Dance Revolution dance mat, which has a USB and controller port version.
Even though the USB ports are supposed to be used exclusively with PlayStation 2 accessories, they have been successfully used with other accessories not designed by Sony.
As the PlayStation 2 has been mostly replaced by its successors, the PlayStation 3 and 4 as of 2014, development of new accessories has been declining steadily.