U.S. television is digital; but not all digital T.V. is high definition (HDTV). Switching to digital opened up many more "band widths" than were available with analogue signals. As a result, the number of over-the-air channels has just about tripled. Many of those new channels are "specialty" channels: foreign language, religious, home shopping, public, weather, etc..
Unfortunately, the digital signal is much weaker and much more directional than the old analogue signal. That's why the "booster button" and rotating antennae are so important to receiving a good, clear signal. My old trailer didn't have an outside antennae, so I had to use digital "rabbit ears" or a digital flat antennae. Still couldn't get many stations: 1-3 at most. The "boosted" antennae on my Eagle is great! I can now pick up 23-25 channels at home, and (generally) 3-10 while camping.
Is this a great country, or what?