Who says radio is dead? These days, we have AM, FM, XM and Sirius satellite radio, Internet radio and HD Radio. So what’s HD Radio?

First of all, don’t confuse it with HDTV. The “HD” in the radio format does not mean “high definition,” though there are some similarities in improved performance. Some believe the HD stands for “hybrid digital,” but the HD in the name is simply part of the trademarked logo.

No matter, though it does helps to think of HD Radio as both higher definition and hybrid digital. Basically, it’s meant as an audible improvement on our AM and FM stations, with less interference and fewer dropouts. With an HD radio—and you’ll need one to get it—FM should sound like CD quality, and AM should sound like FM. The other thing HD Radio does is allow the stations to multicast, or broadcast more than one station, so you can find programming for specific interests. The digital station an HD radio will pick up is broadcast along with the old analog signal, making it hybrid digital.

To enjoy digital multicasts, you’ll need an HD Radio capable of receiving HD2 signals. More than 1,300 stations are now broadcasting signals for HD Radio, so if you live near a major metropolitan area, chances are good you can hear some radio in this new format. (Check out www.hdradio.com to find stations that broadcast near you.)

Best of all? The programming is free; you’ll just need to pay for the HD Radio. And some stations are making their multicast programs commercial-free for awhile. Will that be enough to turn you away from Howard and the satellite radio barrage? We don’t know, but if you want free radio programming, an HD Radio may be worth investigating.