The most visible effect of the Great Compromise of 1787, also called the Connecticut Compromise after the two delegates from that state who proposed it, was to set the shape of the American government's representative structure. It was an agreement worked out between large states, such as Virginia and New York, and small states, such as Rhode Island and New Hampshire, to split the Congress between proportional and general representation.
Under the terms of the compromise, each state's congressional delegation would be split between representatives, who would be elected by district and serve in the House of Representatives, and senators, who would represent their state in the upper house of Congress. This system struck a balance between the demands of the large states for proportional representation in the Legislative Branch, while addressing the concerns of the less-populous states that their interests would be ignored or overridden by the much larger delegations of big states.
The practical effect created a two-tiered system in which the needs of the people could be addressed in the lower house of Congress, and the competing interests of the states could be handled in an upper house where each state enjoys an equal voice. This split between direct and indirect representation would later influence the formation of the Electoral College and the election of presidents.