Overview
A member of congress (MOC) is a person who has been appointed or elected and inducted into an official body called a congress, typically to represent a particular constituency in a legislature. The term member of parliament (MP) is an equivalent term within a parliamentary system of government.
United States
In referring to an individual lawmaker in that person's capacity of serving in the United States Congress, a bicameral federal legislature, the term Member of Congress is used less often than other terms in the United States. This is because in the United States the word Congress is used as a descriptive term for the collective body of legislators from both of its houses: the Senate and the House of Representatives.
While a reference to a member of the Senate is typically referred to quite straightforwardly as Senator (followed by "name" from "state"), a member of the House of Representatives is typically idiomatically referred to as Congressman or Congresswoman (followed by "name" from the "number" district of "state"); or, removing any ambiguity, Representative ("name" from the "number" district of "state"). Although senators are members of Congress, they are not normally referred to or addressed as "Congressman" or "Congresswoman".
Members of Congress in both houses are elected by direct popular vote. Senators are elected via a statewide vote and representatives by votes in each congressional district. Congressional districts are apportioned to the states, once every ten years, based on population figures from the most recent nationwide census. Each of the 435 members of the House of Representatives is elected to serve a two-year term representing the people of that person's district. Each state, regardless of its size, has at least one representative. Each of the 100 members of the Senate is elected to serve a six-year term representing the people of that person's state. Each state, regardless of its size, has two senators. Senatorial terms are staggered, so every two years approximately one-third of the Senate is up for election. Each staggered group of one-third of the senators is called a 'class'. No state has both its senators in the same class.
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