* Hamlet: He is the first to encounter the ghost and interacts with it most extensively. He is deeply affected by the ghost's revelations and driven to revenge.
* Horatio: Hamlet's close friend, Horatio witnesses the ghost with Hamlet and is initially skeptical but ultimately believes in its veracity. He acts as a confidant and advisor throughout the play.
* Marcellus and Bernardo: The two guards who first encounter the ghost and report it to Hamlet and Horatio. They do not directly interact with the ghost but are present for the initial sighting.
Important Note: While other characters, like Gertrude (Hamlet's mother) and Claudius (Hamlet's uncle), are told about the ghost, they do not see or hear it directly. This adds to the mystery surrounding the ghost's existence and the play's themes of doubt, reality, and deception.