and thus all three seek to right the injustices they have suffered. Hamlet wants to avenge his father's death (at least he gives it great thought for much of the play). Laertes wants Hamlet to pay for the death ofPolonius, and he also seeks justice for Hamlet's mistreatment of his sister and Hamlet's former lover, Ophelia. And Fortinbras wants to reclaim the Norwegian territory on behalf of his father's honor. Beyond that, the three are pretty different.

Hamlet is a man of inaction. He can't decide whether the ghost is real or not. He can't decide if he should kill Claudius or not. He breaks his commitments to Ophelia and wallows in self-pity (whether real or feigned to achieve his own purposes) for much of the play. He only decides to really move forward against Claudius after he accidentally kills Polonius.

Laertes, on the other hand, immediately returns home from France when news reaches him of the murder of his father. He doesn't need to weigh out the advantages and risks; Laertes is ready to avenge his father's death without further question.

While Hamlet ponders the meaning of life in his famous "To be or not to be" soliloquy, Fortinbras is out raising an army to reclaim what he feels is rightfully his. He is also a man of action (like Laertes) and also answers to his uncle who has become king following the death of his father (like Hamlet).

However, Fortinbras earns the respect of Hamlet in the final scene, with Hamlet acknowledging and supporting the soon-to-be new king of Denmark: "But I do prophesy the election lights / On Fortinbras. He has my dying voice" (5.2.383–384). Perhaps Hamlet sees in Fortinbras the leader he wanted to be or the path he wishes he could have taken.

Though Hamlet and Laertes take completely different approaches to revenge, they both end up equally dead in the final scene, perhaps showing that the calculated yet steady movements of Fortinbras are worthy of the most respect.

In Shakespeare's Hamlet, Fortinbras and Laertes serve as foils to Hamlet.  They present alternative ways of handling the same situation that Hamlet is in.  They suffer the loss of their fathers, as Hamlet does.

Fortibras sets out to attack Denmark to avenge the death of his father in battle against Denmark, but is stopped by his uncle, who is now king of Norway.

Laertes storms in to Elsinore intent on killing Claudius, who he thinks had a part in the death of his father, Polonius. 

Neither of these alternatives are necessarily better, they are just alternatives.  Laertes, in particular, is hot headed and dishonorable.  He allows himself to be manipulated by the king and hatches a plan to poison Hamlet.

And Hamlet does more than just sit around and worry.  His character is considered to be one of the great thinkers of English literature.  And there are numerous possibilities that might cause him to delay his revenge:  he is unsure of the Ghost's identity for the first half of the play; he is suffering from depression and maybe madness; it is not a small thing to kill a king; he doesn't want to send Claudius to heaven by killing him while he is confessing his sins, etc. 

But, for better or worse, Fortinbras and Laertes do serve as foils to Hamlet.

All three men try to take revenge for fathers murdered, but each are delayed in doing so, and each regret the act after:

Fortinbras takes political action to avenge his father's death.  Old Fortinbras was killed by Hamlet Sr., and Hamlet Sr. was already killed by Claudius, so Fortinbras decides to wage war on the entire state of Denmark.  He tries to be a man of action, but he is called back by his uncle, the sick king of Norway.  So, he wages war on Poland instead.  In the end, when he reaches Denmark all are dead, and though his invasion is bloodless, he never really enacts personal revenge.  He is the only avenger standing, a lonely enterprise.

Laertes tries to take quick and personal revenge for his father's murder, first on Claudius.  Claudius advises that he wait and kill Hamlet during a rigged fencing match.  After he is stabbed, he regrets his role as avenger because he has been used as a tool for Claudius' revenge.  In the end, quick personal revenge causes one to be manipulated.

Hamlet is caught between revenge and mercy, mainly because of fear of damnation and problems with his mother.  His father mandates revenge, though Hamlet is unprepared to do so.  He delays revenge because of fear and supernatural misgivings: how to send Claudius to hell and his father and himself to heaven (is it even possible?).  In the end, he enacts revenge on Claudius, but it comes after he is killed.  He has lost everything: mother, girlfriend, and his own life.

To me, the major similarity between these three young men is that each of these men feels (at some point in the play) that his family has been wronged and he needs to take revenge.  Hamlet, of course, has had his dad killed.  Fortinbras's father was killed too, and part of his kingdom taken.  For Laertes, the wrong is later in the play, but his dad has been killed too.

What's different about them, to me, is that Laertes and Fortinbras are confident men of action.  They act quickly to take revenge.  Hamlet, on the other hand, is famous for sitting around worrying about what he should do instead of actually doing something.

The main difference among the three characters is the ability or lack of ability to act decisively.  Throughout the first four and half acts of the play, Hamlet wrestles with whether or not he should avenge his father's death and then how he should proceed with the revenge.  As soon as Laertes finds out his father was killed, he immediately demands revenge.  Fortinbras goes to the extent to lie to his uncle in order to exact his revenge against Denmark for his father's death.  Both Laertes and Fortinbras act without delay and with determination while Hamlet struggles in a sea of indecision.

Fortinbras is decisive and warrior-like whereas Hamlet vacillates and is much more peace-loving.  Fortibras is willing to conquer a relatively useless piece of land simply to enlarge the conquests of his kingdom:  (Truly to speak, and with no addition,We go to gain a little patch of ground / That hath in it no profit but the name. To pay five ducats, five, I would not farm it;Nor will it yield to Norway or the Pole / A ranker rate, should it be sold in fee (4.4.119-125). 

Laertes is easily led while Hamlet needs to be sure of everything before he makes a move, yet he feels stymied by doubt, as evidence in his famous "To be or not to be" soliloquy (Act 3.1).  But Laeretes is all to ready to believe the worst, and be sucked in by Claudius' deceit, becoming a pawn to his deadly games.