Discovery Communications LLC is an American mass media company based in Silver Spring, Maryland. The company operates a variety of television networks including Discovery Channel, Animal Planet, TLC, and Investigation Discovery. It is also the parent company of other media brands and entities such as Eurosport, the digital platform Eurosport Player, the global television production company All3Media, the publishing company Discovery Press, and the web-based video service Discovery Digital Networks. Founded by John Hendricks in 1985, Discovery Communications is one of the largest content companies in the world.