"Sunday" comes from The Cranberries' debut album, Everybody Else Is Doing It, So Why Can't We?, an album entirely written by lead singer Dolores O'Riordan and guitarist Noel Hogan. The album helped the Irish rock band achieve international fame. While specific lyrical meanings for "Sunday" aren't detailed, the band's sound often blended alternative rock with elements of jangle pop, dream pop, and folk rock. This song, released as a promotional single in the US, offers a glimpse into the early world of a band that would go on to create powerful, anthemic music. Playing "Sunday" can feel like stepping into the band's formative sound, full of their signature blend of introspection and melodic energy.