This infographic created by Jason at Frugal Dad shows that almost all media comes from the same six sources.

That's consolidated from 50 companies back in 1983.

NOTE: This infographic is from last year and is missing some key transactions. GE does not own NBC (or Comcast or any media) anymore. So that 6th company is now Comcast. And Time Warner doesn't own AOL, so Huffington Post isn't affiliated with them.

https://www.businessinsider.com/these-6-corporations-control-90-of-the-media-in-america-2012-6