The Great Compromise was the set of discussions during the Constitutional Convention that led to the creation of the Senate and the House of Representatives. At the core of the Compromise was the idea that states with more people should have a greater say than states with fewer (which is why each states' seats in the House of Representatives is tied to population); however, it also believes that those smaller states should not be overrun and out-represented to the point that they have no say in the government. To solve that, each state was given equal representation as well (which is why each state, no matter its size, has two Senators).
Overall, the goal of the Great Compromise was to ensure that while larger states have a greater say, that say does not come at the expense of smaller states who have the ability to challenge in the Senate.
