Short answers, pulled from the story.
Prince Hamlet is the title character and protagonist of William Shakespeare's tragedy Hamlet, written between 1599 and 1601. He is the Prince of Denmark, son of the murdered King Hamlet, and nephew to the usurping King Claudius.
The name Hamlet derives from Amleth, a figure in a 13th-century book of Danish history by Saxo Grammaticus, later popularized in French by Francois de Belleforest as L'histoire tragique d'Hamlet. The Old Icelandic root amlodi means fool, while the deeper etymological root carries the meaning furious, raging, wild.
Hamlet's age is a longstanding scholarly debate. A gravedigger in act five implies Hamlet is 30, and the actor who first played the role, Richard Burbage, was 32 at the time. However, evidence in the First Quarto and First Folio suggests an earlier version of the play may have presented Hamlet as 16 or 17.
Hamlet gives two reasons for delaying. First, he devises a play to verify the ghost's accusation before acting. Second, when he catches Claudius alone, Claudius is at prayer, and Hamlet refuses to kill him in that state because he believes death at that moment would send Claudius to heaven rather than to damnation.
Ernest Jones, following Sigmund Freud, argued in his essay The Oedipus-Complex as an Explanation of Hamlet's Mystery: A Study in Motive that Hamlet's paralysis stems from an Oedipus complex. Jones held that Hamlet cannot kill Claudius because doing so would mean killing the man who married his mother, a desire he has suppressed in himself.
Notable performers include Sir Henry Irving, who played the role for 200 consecutive performances at the Lyceum Theatre in 1874, John Gielgud who performed it over 500 times between 1930 and 1945, and Laurence Olivier who directed himself in the 1948 Academy Award-winning film. More recently, Benedict Cumberbatch played the role at the Barbican Centre in London in 2015, and Kenneth Branagh's 1996 film remains the only full-length version of the play on film.