Short answers, pulled from the story.
King Tim III (Personality Jock) is a 1979 hip hop song by the Fatback Band, released on the 25th of March 1979 as the B-side of a single from their disco album Fatback XII. It is often cited as the first recorded hip hop song released to the mass market, predating Rapper's Delight by a few months.
King Tim III is the stage name of Timothy Washington, a little-known MC and DJ who was brought in to rap over the Fatback Band's instrumental track. Washington reportedly had a connection to the band through Anthony Bee, one of Fatback's roadies.
King Tim III (Personality Jock) was released on the 25th of March 1979. It was originally the B-side of a single, with You're My Candy Sweet as the A-side, but Spring Records later reissued the single with the sides switched after the rap song outperformed the A-side.
King Tim III (Personality Jock) peaked at number 26 on the Billboard R&B chart and remained on the chart for 11 weeks. The A-side You're My Candy Sweet only reached number 67 and stalled after four weeks.
Bandleader and percussionist Bill Curtis felt that Fatback XII lacked a potential hit while finishing the album. He decided to add rapping over an existing mostly instrumental track called Catch the Beat after being exposed to hip hop through cassette tapes and seeing DJ Hollywood perform at the Apollo Theater.
King Tim III (Personality Jock) was released a few months before Rapper's Delight in 1979 and is cited as the earlier commercially released hip hop recording. Rapper's Delight is widely regarded as the first commercially successful hip hop song due to its greater commercial impact.