Radio Single

A promotional recording, or promo, is an audio or video recording distributed for free, usually in order to promote a recording that is or soon will be commercially available. Promos are normally sent directly to broadcasters, such as music radio and television stations, and to tastemakers, such as DJs and music journalists, in advance of the release of commercial editions, in the hope that airplay, reviews, and other forms of exposure will result and stimulate the public's interest in the commercial release.

Promos are often distributed in plain packaging, without the text or artwork that appears on the commercial version. Typically a promo is marked with some variation of the following text: "Licensed for promotional use only. Sale is prohibited." It may also state that the promo is still the property of the distributor and is to be "returned upon demand." However, it is not illegal to sell promotional recordings, and recalls of promos are extremely rare and unenforced.

Because promos are produced in smaller quantity than releases made available to the general public, they are sometimes considered valuable collectors' items. They are never intended for sale in record stores.

A promo single (short for promotional single) is a single that is made available to radio stations, nightclubs, music publications, and other media outlets by a record label for the express purpose of promoting a forthcoming commercial single or an entirely new album. A song may be released as a promotional single even if no commercial version of the single is available to buy. This is usually for the purpose of promoting an entire album. While intended specifically for use by professional disc jockeys and not for resale, they are frequently sought out by music collectors nonetheless.

The promo single is usually recognized by its limited liner notes and cover artwork as well as its unique catalog number (or the occasional lack thereof). Quite often, vinyl records will be issued in a generic cardboard jacket or white paper sleeve while CDs will be issued in a slimline jewel case or cardboard sleeve.

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Wikipedia