Logo.
Sony is a video game company, and one of Nintendo's biggest competitors.
PlayStation
The classic PlayStation
The PlayStation was the first home console produced by Sony Computer Entertainment. It was released in 1994 and has sold 102.49 million units. It resulted from a failed joint project between Nintendo and Sony. Sony was designing a disc-playing peripheral for the Super Nintendo and the deal went awry. Sony left and developed their own console, the PlayStation.
PSone
The PSone, launched in 2000, is Sony's smaller (and redesigned) version of its PlayStation. The PSone is about one-third smaller than the original PlayStation and went on to outsell all other consoles including Sony's own brand-new PlayStation 2 throughout the remainder of the year. They even started releasing PSones with screens so you didn't have to play in front of the television which is similar to the Wii U.
PlayStation 2
PlayStation 2
The successor to the PlayStation was the PlayStation 2. Unlike the PlayStation, it is a multi-regional console as it could also be used as a DVD player, this is something that Nintendo did not add to their consoles; the PlayStation 2 also had backwards compatiblity with PlayStation games, including the use of the Dualshock. Since its release in 2001, the PlayStation 2 has sold over 150 million units as of January 31, 2011, making it the best-selling console of all time.
Slim case design
The slim lined version of the original PlayStation 2 has a few improvements over the original with a quieter fan and the option to go online and play online games straight from the box as apposed to getting a adaptor for the original.
PlayStation 3
PlayStation 3
The PlayStation 3 is the latest in the PlayStation range offering more in the way in terms of functions compared its predecessors. It was released within two days of the Wii, though about a year after the Xbox 360, which gained a dramatic head start. It features Blu-ray compatibility. Backward compatibility is limited, however, depending on the model. Sony currently hasn't said anything about releasing a PlayStation 4 nor an upcoming console.
PlayStation Portable
PlayStation Portable
The PlayStation Portable was released several weeks after the Nintendo DS and does not feature a clamshell design although it did feature multimedia since it's release in 2004 which is something nintendo didn't do until the Nintendo DSi came out in 2009. Even though the PSP has multimedia, you need to plug in a camera acsessory if you want to work the camera unlike the DS. The PSP was later succeeded by the PlayStation Vita in 2012.
PlayStation Vita
PlayStation Vita
The PlayStation Vita was released on December 18, 2011 in Japan and February 22, 2012 in other reigons. It competes against Nintendo's 3DS which is a year older than the PSVita. Once again the Nintendo 3DS still features it's clamshell design while the PSVita doesn't. The PSVita now also has a built in camera with video except you can't grafitti on it or add any special effects, and lastly, the PS Vita takes cards instead of UMDS, and has a touchscreen as well as an optional touchpad at the bottom.