In the play, Othello, the handerchief serves as the item.... the proof..... that will lead to Desdemona's undoing. At first, we have no suspicions about the handkerchief, as Shakespeare leaves the audience ignorant of its purpose. Emilia obviously hands the handkerchief to her husband without malice and completely oblivious as to his intent. None-the-less, this very small item was of utmost importance to Othello..... it was a symbol of his love, and Iago is able to make him believe that it was given away without hesitation. In some instances this wouldn't make any difference, but Othello is a jealous man, and Iago is well aware of his weakness, so he uses it.... feeding Othello's suspicions until the man goes mad.