How are Macduff, Macbeth and Banquo different from each other?

First, it will be helpful to examine of each of these characters as individuals.

MACBETH - Macbeth is the central character of the play. Before arriving onstage, he is described as being brave and able to cut a man from "nave to th'chops" (I.i.24). Whether or not this description can be trusted, it is clear that Macbeth is believed to be a very strong and courageous warrior. At the beginning of the play, Macbeth listens...

First, it will be helpful to examine of each of these characters as individuals.

MACBETH - Macbeth is the central character of the play. Before arriving onstage, he is described as being brave and able to cut a man from "nave to th'chops" (I.i.24). Whether or not this description can be trusted, it is clear that Macbeth is believed to be a very strong and courageous warrior. At the beginning of the play, Macbeth listens to those around him and shows great charisma. However, Macbeth becomes a very ambitious and greedy character. His vaulting ambition drives him to commit murders in the play, and this ambition is ultimately his downfall. 

MACDUFF - Macduff is a Scottish noble and is often described as Macbeth's foil. Similarly to Macbeth, Macduff is a warrior. However, Macduff publicly feels emotions and is seen as a relatable character, specifically when his family is murdered and he becomes quite emotional. He is a character of great humanity and he often makes decisions based on his values and his honor. He does not profess empty rhetoric. Macduff can be trusted.

BANQUO - Banquo is an extremely likable character. He shows restraint and is suspicious of the witches. Banquo is loyal to Macbeth and he is kind to his son, Fleance. Banquo is one of the few characters the audience sees parenting a child, and so Banquo becomes one of the central father figures in the play. 

Macduff and Macbeth are the most obviously different. Macbeth frequently announces lies and coerces and deceives. Macduff, however, is true to his word. He does not state things he does not know to be true. Both of these men are warriors. Banquo, while also a fighter, is the most relatable character out of the three. He is not prone to hysteria, and he is more loyal than ambitious.