"1234" (pronounced "One Two Three Four") is a song from Feist's third studio album, The Reminder. It is Feist's most successful single to date. The song was co-written by Sally Seltmann, an Australian singer-songwriter who also recorded under the stage name New Buffalo, and Feist. It remains Feist's biggest hit single in the USA to date, and her only song to chart on the Billboard Hot 100 and UK Top 40.

In an interview with Songfacts, Sally Seltmann said:

I had been listening to Feist's album Let It Die. I thought my little song about lost love, and the hope to recapture what you once had, sounded too much like a Feist song for me to use for New Buffalo, so I shelved it. Then, in late 2005 I did a tour across Canada supporting Feist, and Broken Social Scene. After meeting Feist, I started to wonder whether she might like to do a cover of "1234," but I was too shy to tell her about it. At the last Broken Social Scene show, I plucked up the courage to tell her that I had written a song which I thought she might like to use. We went onto the tour bus, and I recorded a simple version of the song into her laptop, with guitar and vocals. To my surprise, she loved the song, and started playing it live.

Year 1234 (MCCXXXIV) was a common year starting on Sunday (link will display the full calendar) of the Julian calendar.

In music, a song is a composition for voice or voices, performed by singing. A song may be accompanied by musical instruments, or it may be unaccompanied, as in the case of a cappella songs. The lyrics (words) of songs are typically of a poetic, rhyming nature, though they may be religious verses or free prose.

A song may be for a solo singer, a duet, trio, or larger ensemble involving more voices. Songs with more than one voice to a part are considered choral works. Songs can be broadly divided into many different forms, depending on the criteria used. One division is between "art songs", "pop songs", and "folk songs". Other common methods of classification are by purpose (sacred vs secular), by style (dance, ballad, Lied, etc.), or by time of origin (Renaissance, Contemporary, etc.).

A song is a piece of music for accompanied or unaccompanied voice or voices or, "the act or art of singing," but the term is generally not used for large vocal forms including opera and oratorio. However, the term is, "often found in various figurative and transferred sense (e.g. for the lyrical second subject of a sonata...)." The noun "song" has the same etymological root as the verb "to sing" and the Oxford English Dictionary (OED) defines the word to mean "that which is sung" or "a musical composition suggestive of song." The OED also defines the word to mean "a poem" or "the musical phrases uttered by some birds, whales, and insects, typically forming a recognizable and repeated sequence and used chiefly for territorial defence or for attracting mates."