Talk:Just Dance 2015/@comment-16508462-20140801171951/@comment-12228547-20140802013422

Singles, meaning songs that appear not only on albums. International Smile is different from Dark Horse or Birthday. It is not played on the radio, and is not sold separately off the album. International Smile is not a single.

For example, all songs by Katy Perry before have been singles and are sold not only on the album but also is on the radio.