Horatio

Horatio is Hamlet's most trusted friend, to whom Hamlet reveals all his plans. Several times Hamlet swears his affection to Horatio in a way he does for no other character. Horatio swears himself to secrecy about the ghost and Hamlet's pretense of madness, and conspires with Hamlet to prove Claudius's guilt in the mousetrap play. He is the first to know of Hamlet's return from England, and is with him when he learns of Ophelia's death. Not only is Horatio loyal and supportive, he is also rational. The guards in the opening scene call upon Horatio to bear witness to the presence of the ghost, trusting in his unbiased opinion. Without proof, Horatio is skeptical of the ghost: "Horatio says 'tis but our fantasy,/ And will not let belief take hold of him." The fact that Horatio sees the ghost has been used to refute the theory that the ghost is a figment of Hamlet's imagination. At the end of the play, Horatio proposes to finish off the poisoned drink which was intended for Hamlet,... full article at wikipedia