Cassio, Roderigo, Barbantio and their functions

From Shakespeare's play Othello, this paper will be discussing the roles
of Cassio, Roderigo and Brabantio, and their functions.
First, Cassio. Cassio is an honourable lieutenant and a soldier, who is
very loyal and caring towards his commanding officer, Othello, as shown
in one of many places, act two scene one line 45-48 when he is concerned
about Othello's well being because he has been lost at sea and says:
Thanks, you the valiant of this warlike isle, That so approve the Moor! O,
let the heavens Give him the defense against the elements, For I have lost
him on a dangerous sea
In th…