Because it is made up of two houses what is the description of the US Congress?

The lower house of the U.S. Congress, the House of Representatives, effects representation by population; that is, New York and Florida send a higher proportion of the 435 Representatives to the House than do Rhode Island and Delaware.

The upper house of the U.S. Congress, by contrast, provides equal representation for each of the fifty States. That is, each State, be it California, or Wyoming, sends exactly 2 of the 100 Senators to the U.S. Senate. Therefore, while California has a population of over thirty million, and Wyoming has a population of just over half a million, the former can exercise no greater legislative power in the Senate than the latter. That is, as a group, Wyoming's half-million people are, in the final analysis, due to the Constitutional requirement of bicameralism (requiring identitical legislative enactments by both the House and the Senate as a Constitutional prerequisite to presentment) as politically powerful, in this way, than California's thirty million. That is, California's House caucus, which consists of 53 representatives, is totally offset by Wyoming's Senate caucus, if the two State caucuses were to vote adversely.

The varying modes of representation between the U.S. House and the U.S. Senate are an aspect of our federalism. The idea is that the two varying modes of apportionment, yield a fair, but egalitarian, implementation of legislative democracy.