Horse opera refers to a western movie or television series that is extremely cliche or formulaic (in the manner of a soap opera). The term, which was originally coined by silent film-era Western star William S. Hart, is used variously to convey either disparagement or affection. The name "horse opera" was also derived in part from the musical sequences frequently featured in these films and TV series which depicted a cowboy singing to his horse on-screen. It should be noted that this term is quite loosely defined; it does not specify a distinct sub-genre of the western (as "space opera" does with regard to the science fiction genre).