Does the Bible teach marriage between one man and one woman?

Before I give the answer, I would like to analyze some passages from both the Old and New T.’s. Many people (mostly homosexuals and their atheist friends) claim that the Bible never says anything about marriage between one man and one woman. In fact, they usually bring examples of Old T. personages who had more than one wife, claiming that this is proof that God never intended marriage to be between one man and one woman.