WLIW's main studios and transmitter are located in Plainview on Long Island, while its operations are housed at WNET's studios in Midtown Manhattan.

WLIW's transmitter tower, adjacent to its studios in Plainview, New York, June 2010. The station first signed on the air on January 14, 1969, and was originally operated by the Long Island Educational Television Council. In February 2003, the Long Island Educational Television Council merged with the Educational Broadcasting Corporation (the present-day WNET.org), combining WLIW's operations with those of WNET. The Long Island Educational Television Council was retained as WLIW's governing board and fundraising arm.

WLIW promotes itself as a more locally-oriented station than WNET, as evidenced by its on-air moniker of "New York Public Television." However, it is a major producer of national PBS programming in its own right. Among its more prominent shows are the innovative Visions series and many music specials featuring noted American performers like Frank Sinatra, Billy Joel, Neil Sedaka, Ricky Nelson and international stars like Helmut Lotti and Sarah Brightman. Regular hosts of these specials produced for PBS include Laura Savini, Terrel Cass, Mark Simone, David Rubinson and Lisa Jandovitz.

Its former identity which debuted in 2005, its color palette and on-air graphics, were designed and conceived by Trollback + Company. It was the station's first corporate branding initiative since its launch in 1969. In 2009, WLIW unified its branding with its sister WNET, adopting a similar logo, but in a blue color scheme rather than WNET's red, but keeping the "WLIW 21" brand name; it did, however, carry over the dotted "i" from the WNET logo. It rolled out a new logo in 2012, removing the dotted "i."

Analog-to-digital conversion