wikipedia says: "The Connecticut Compromise (also known as the Great Compromise of 1787 or Sherman Compromise) was an agreement that large and small states reached during the Constitutional Convention of 1787 that in part defined the legislative structure and representation that each state would have under the United States Constitution. It retained the bicameral legislature as proposed by Roger Sherman, along with proportional representation of the states in the lower house or House of Representatives, but required the upper house or Senate to be weighted equally among the states. Each state would have two representatives in the upper house."
