Mister, usually written in its abbreviated form Mr or Mr. (American English), is a commonly used English honorific for men under the rank of knighthood. The title derived from master, as the equivalent female titles, Mrs., Miss, and Ms, all derived from the archaic mistress. The title master was retained and used for boys and young men, but is now less commonly used. The plural form is Misters, or the abbreviation Messrs (UK) or Messrs. (US) ( /ˈmɛsərz/). This is an English abbreviation of the French "messieurs" (French pronunciation: [mesjø]), sometimes pronounced /ˈmɛsərz/ in English.

When addressing someone directly: Mr. is usually used with the last name only ("May I help you, Mr. Thompson?"). In other circumstances, it can be used with either the last name or the full name ("This is Mr. John Smith."; "Would you please help, Mr Smith?"). In formal written address, it is usually used along with the full name, or with initials and surname.

When a man's name is unknown, "mister" is sometimes used informally by itself in direct address, as in, "Hello, mister," or "Are you all right, mister?" rather than the standard form of address, "Sir". Though not necessarily meant disrespectfully, such use may to some people seem rude.

Scott Ramon Seguro Mescudi (born January 30, 1984), better known by his stage name Kid Cudi ( /ˈkɪd ˈkʌdi/ KID KUD-ee), sometimes stylized KiD CuDi, is an American alternative hip hop recording artist, singer-songwriter, guitarist and actor. He first gained major attention after the release of his debut mixtape A Kid Named Cudi. In 2009, his single "Day 'n' Nite" reached the top five of the Billboard Hot 100 and Hot R&B/Hip-Hop Songs charts. "Day 'n' Nite" was included on Cudi's debut album Man on the Moon: The End of Day, which was later certified Gold. In 2010 he released his second studio album Man on the Moon II: The Legend of Mr. Rager, preceded by the release of two singles "Erase Me" and "Mr. Rager". In October 2010, Cudi announced that he would be forming a rock band with Dot da Genius called 'Wizard', later renamed WZRD. Their self-titled debut album was released on February 28, 2012. Kid Cudi has sold over 4.6 million digital singles and has worked with Kanye West, Common, David Guetta and other artists signed to the GOOD Music label.