Douglas Harper's Etymology Dictionary
also IOU, I O U, 1610s, originally as IOV (see V); with punning reference to "I Owe You."
Wikipedia
"I.O.U." is a song from 1983 by British musical group Freeez, their most successful hit.
The song scored #2 in the UK Singles Chart earlier in 1983 before reaching the top of the Billboard Hot Dance Club Play chart in the U.S., giving them their only chart-topping single on any chart in America. It then became the 20th best-selling single of 1983 in the United Kingdom. "I.O.U." was used for the 1984 breakdance movie, Beat Street. The chorus is often erroneously sung by listeners as "A-E, A-E I-O-U and sometimes Y", referring to the vowels of the alphabet. It is actually "A-E, A-E, I-O-U I sometimes cry" and "A-E, A-E, I-O-U I sometimes lie". The music video for "I.O.U." featured on the video version of Now 1 but the song itself did not appear on the album version.
During 1986 a 12" single was released in the US by the Criminal Records company, with new remixes. Some of these remixes were given a re-release during 1987 in the UK for the Citybeat label as "I.O.U. (The Ultimate Mixes '87)", however, it only scored #23 in the UK Singles Chart this time.
I.O.U. is the second studio album by guitarist Allan Holdsworth, released in 1982 through Luna Crack Records/I.O.U. Records originally on vinyl; a CD edition was reissued in 1985 through Enigma Records and a remaster in 2008 through Belle Antique. A previous album, Velvet Darkness, was released in 1976 without Holdsworth's consent, therefore making this (in his view) his first official solo release. Furthermore, many tracks from Velvet Darkness were remade and retitled for I.O.U..
"I.O.U. (I Owe You)" is a song written by Kerry Chater and Austin Roberts, and performed by American country music artist Lee Greenwood. It was released in March 1983 the first single from his album Somebody's Gonna Love You. The single peaked at number 6 on the U.S. country charts and number 4 in Canada. It also peaked at number 4 on the U.S. adult contemporary charts. Other than "God Bless the USA", it is Greenwood's biggest crossover hit, peaking at number 53 on the Billboard Hot 100.
I.O.U., an acronym for Inside Our Universe, is an American hip hop duo from New Brunswick, New Jersey. I.O.U. initially started as two college friends from Rutgers who remixed Wiz Khalifa hit song Black and Yellow to the tune of Black and Scarlett, Rutger's official colors. The song was a hit on YouTube and the duo started working full time on music. Since then they've opened for the likes of Far East Movement and Rick Ross.
I.O.U. is a song written by Jimmy Dean and Larry Markes, and recorded most famously by Dean. A recitation with an instrumental backing that paid homage to mothers and motherhood, "I.O.U." became Dean's first top 10 country hit in 10 years and briefly sparked the comeback of sentimental-style recitations.