A generic term for [[ExactlyWhatItSaysOnTheTin dramatic series that run in a one-hour time slot]]. Along with the SitCom and the RealityShow, one of the three primary non-news, non-sports television programming types found on American TV. The term is purely a type descriptor, and conveys no indication of level of humor or high drama on the show, or lack thereof.
Of course, an "hour-long" TV program is usually not really an hour long unless it's on TheBBC. More like 40-42 minutes plus commercials.