Thelonious Sphere Monk was born two years after his sister Marion on October 10, 1917, in Rocky Mount, North Carolina, and was the son of Thelonious and Barbara Monk. His badly written birth certificate misspelled his first name as "Thelious" or "Thelius." It also did not list his middle name, taken from his maternal grandfather, Sphere Batts. A brother, Thomas, was born in January 1920.

In his early teens, Monk toured with an evangelist, playing the church organ, and in his late teens he began to find work playing jazz. In the early to mid-1940s, he was the house pianist at Minton's Playhouse, a Manhattan nightclub. Much of Monk's style was developed during his time at Minton's, when he participated in after-hours cutting contests, which featured many leading jazz soloists of the time. Monk's musical work at Minton's was crucial in the formulation of bebop, which would be furthered along by other artists, including Dizzy Gillespie, Charlie Christian, Kenny Clarke, Charlie Parker, and, later, Miles Davis. Monk is believed to be the pianist featured on recordings Jerry Newman made around 1941 at the club. Monk's style at this time was later described as "hard-swinging," with the addition of runs in the style of Art Tatum. Monk's stated influences included Duke Ellington, James P. Johnson, and other early stride pianists. In the documentary Thelonious Monk: Straight, No Chaser, it is stated that Monk lived in the same neighborhood in New York City as Johnson and knew him as a teenager.  Mary Lou Williams, who mentored Monk and his contemporaries, spoke of Monk's rich inventiveness in this period, and how such invention was vital for musicians, since at the time it was common for fellow musicians to incorporate overheard musical ideas into their own works without giving due credit. "So, the boppers worked out a music that was hard to steal. I'll say this for the 'leeches,' though: they tried. I've seen them in Minton's busily writing on their shirt cuffs or scribbling on the tablecloth. And even our own guys, I'm afraid, did not give Monk the credit he had coming. Why, they even stole his idea of the beret and bop glasses."  In 1944 Monk made his first studio recordings with the Coleman Hawkins Quartet. Hawkins was one of the earliest established jazz musicians to promote Monk, and the pianist later returned the favor by inviting Hawkins to join him on a 1957 session with John Coltrane.

Answer the following question by taking a quote from the article: What instruments did he play?
In the early to mid-1940s, he was the house pianist at Minton's Playhouse,