UHF or VHF or DTV or HDTV – Do I need them all?

[asps400]

I recently visited my son and stayed in his travel trailer. He hooked up a digital TV that I watched before the digital transition (he lives in Loomis, CA 95650.) Before the digital cut over I got about 10 channels that came in poorly. We hooked up the TV to the trailer antenna and immediately got over 20 very clear channels with his existing antenna. Now I am looking for a digital TV that I can also take traveling.

Apparently existing OTA antenna’s work good but I would like some clarification.

Do I need a UHF/VHF antenna for digital?

Are there digital channels that use VHF and other digital channels that use UHF?

Is there a difference between a DTV antenna and an HDTV antenna?

What is the difference between Omni Directional and Directional Antenna’s (besides the obvious.)

[asps400]

P.S. I forgot to mention that we did not rotate his antenna although it may have already been pointing in the right direction. There are also a lot of trees and rolling hills. I was really amazed at picture quality and number of channels.