30 Rockefeller Plaza (officially the Comcast Building; formerly RCA Building and GE Building) is a skyscraper that forms the centerpiece of Rockefeller Center in the Midtown Manhattan neighborhood of New York City, New York. Completed in 1933, the 66-story, 850 ft (260 m) building was designed in the Art Deco style by Raymond Hood, Rockefeller Center's lead architect. 30 Rockefeller Plaza was known for its main tenant, the Radio Corporation of America (RCA), from its opening in 1933 until 1988 and then for General Electric until 2015, when it was renamed for its owner Comcast. The building also houses the headquarters and New York studios of television network NBC; the headquarters is sometimes called 30 Rock, a nickname that inspired the NBC sitcom of the same name. The tallest structure in Rockefeller Center, the building is the 28th tallest in New York City and the 65th tallest in the United States, and was the third tallest building in the world when it opened.
30 Rockefeller Plaza's massing consists of three parts: the main 66-story tower to the east, a windowless section at the center, and a 16-story annex to the west. The building's design conforms with the 1916 Zoning Resolution; it is shaped mostly as a slab with setbacks primarily for aesthetic value. The facade is made of limestone, with granite at the base, as well as about 6,000 windows separated by aluminum spandrels. In addition to its offices and studios, 30 Rockefeller Plaza contains the Rainbow Room restaurant and an observation deck called Top of the Rock. 30 Rockefeller Plaza also includes numerous artworks and formerly contained the mural Man at the Crossroads by Diego Rivera. The entire Rockefeller Center complex is a New York City designated landmark and a National Historic Landmark, and parts of 30 Rockefeller Plaza's interior are also New York City landmarks.