How does Shakespeare establish characters and theme in the opening act of "Macbeth"?

Shakespeare's characters and themes in "Macbeth" are strongly developed right from the beginning. Shakespeare uses a variety of techniques to establish his themes and characters, via the dialogue and stage directions in his play. The introductory actions of the characters, along with the location and weather of the scene, work in conjunction with the language devices to quickly establish the key characters and themes.
A prominent theme of Macbeth is the supernatural. Shakespeare uses the witches as the centre of the supernatural and mystery in the play. Shakespeare establishes an atmospher…