PlayStation's motion sensing camera has gone through three iterations, each with its own name and form factor.
The Playstation 2 EyeToy USB Camera was released in 2003, well before the Xbox Kinect, which came out in 2010. EyeToy uses a single camera along with special motion tracking software to place an image of your body in a game environment. It tracks your movements in 2-D, meaning where your hands and other parts are located on the flat plane of the screen, allowing you to manipulate objects in a game to score points.
In fact, all of the camera iterations use sophisticated algorithms to display your image on the screen and let you manipulate a virtual game environment in various ways. The environment just got a lot less two dimensional than where it started with EyeToy.
Sony released the PlayStation Eye Camera in 2007 for its PlayStation 3 console. It was a similar, single camera motion sensing unit, but more bubbly in shape. In 2010, the company released PlayStation Move controllers that worked in conjunction with Eye to greatly augment its capabilities. The Eye could sense 3-D motion by detecting the position and relative size of a glowing ball at the end of the Move controller. The ball also glowed in various colors so that the Eye could differentiate between players.
In early press releases from Sony, the latest generation camera was referred to as the PlayStation 4 Eye, but the name was changed to PlayStation Camera before it launched in late 2013. And it underwent some major changes from the two previous versions.
The shape changed entirely; it became much smaller and it incorporated the second camera, giving it the ability to sense depth on its own without something like the Move. But it can also sense the DualShock 4 controller's light bar, or even the old Move controller, for added accuracy and user differentiation.
The EyeToy only incorporated a single microphone for recording basic voice messages to go along with video, but the PlayStation Eye and the new PlayStation Camera both have four-microphone arrays for sophisticated voice capture and player detection.
The camera specs have predictably changed over the years, too. The EyeToy has 640 by 480 pixel resolution, and rather than fixed focus, its focus can be adjusted manually. The Eye captures 640 by 480 pixels at 60 fps or 320 by 240 pixels at 120 fps, and its field of view is either 56 degrees (normal) or 75 degrees (wide-angle), depending on whether it is zoomed in or out. Both modes are fixed-focus (not adjustable). PlayStation Camera stepped beyond these and into high-def with its max of 1280 by 800 pixels.
EyeToy came bundled with 12 games; many more came out for it and also for the Eye. PlayStation Eye could also be used with a well-received and free photo and video editing program called "EyeCreate" that allowed color-filtered, time lapse and stop-motion video capture. Time will tell if similarly useful programs will be released for the new PlayStation Camera.