1. Hamlet's Strange Behavior: Horatio informs the others about Hamlet's unusual and melancholic behavior. He mentions that Hamlet has become withdrawn, wearing somber black clothes and acting strangely since the death of his father, King Hamlet.
2. Hamlet and the Ghost: Horatio shares the story of the ghost that Hamlet has encountered. He explains that the ghost, resembling the late King Hamlet, has appeared to Hamlet on multiple occasions, revealing dark secrets and seeking revenge.
3. Hamlet's Plan: Horatio reveals that Hamlet is planning something and appears to have a scheme in mind. He mentions Hamlet's cryptic language and indicates that Hamlet may be devising a strategy to avenge his father's death and expose the truth about the events surrounding his death.
4. Concerns for Hamlet: Horatio expresses his concerns about Hamlet's mental state. He worries that Hamlet's preoccupation with revenge and his interactions with the ghost are taking a toll on his sanity and well-being.
5. Arrival of Rosencrantz and Guildenstern: Horatio informs the others that two courtiers, Rosencrantz and Guildenstern, have arrived at the castle upon the king's request. They are tasked with observing Hamlet and understanding the reasons behind his strange behavior.
Through these pieces of news, Horatio provides insights into Hamlet's state of mind, his encounter with the ghost, his plans for revenge, and the challenges he faces. This information contributes to the overall plot development and creates intrigue among the characters.