It is the largest broadcasting and cable television company in the world by revenue, the second largest pay-TV company after AT&T, the largest cable TV company and largest home Internet service provider in the United States, and the nation's third-largest home telephone service provider. Comcast services U.S. residential and commercial customers in 40 states and in the District of Columbia. As the owner of the international media company NBCUniversal since 2011, Comcast is a producer of feature films and television programs intended for theatrical exhibition and over-the-air and cable television broadcast, respectively.

Ralph Roberts : founder of Comcast

 

Comcast owns and operates the Xfinity cable/telecommunications service, over-the-air national broadcast network channels (NBC and Telemundo), multiple cable-only channels (including MSNBC, CNBC, USA Network, NBCSN, and E!, among others), the film studio Universal Pictures, and Universal Parks & Resorts.

Comcast is sometimes described as a family business. Brian L. Roberts, chairman, president, and CEO of Comcast, is the son of co-founder Ralph Roberts. Roberts owns or controls about 1% of all Comcast shares.

 According to wikipedia