Although many antennas are marketed as HDTV antennas, the truth is that all television antennas are capable of receiving both analog and digital signals, including HDTV signals. In most cases, a multidirectional amplified antenna with a power adapter will get the best range of channels. However, in some circumstances you might need a directional antenna. If you're having serious reception problems, choose an outdoor antenna, which gets stronger signals than an indoor antenna. Although many digital stations transmit signals on the UHF band, there are still some that broadcast on high band VHF. For best reception, choose an antenna that can receive both VHF and UHF signals. However, take caution, because many HDTV antennas can only receive a UHF signal. For more information about the HDTV television stations in your area and the different types of antennas, check AntennaWeb.org.
Sources:
"Frequently Asked Questions," http://www.dtv.gov/topfaqs.html