When members of Congress are needed in the Capitol for a vote, bells and buzzers go off in every room of the office buildings. Then the lawmakers leave committee rooms and rush to catch a special underground train that takes them to the Capitol. Usually, they're on time to cast their vote or make a short speech. They represent the people who elected them to office. Senators represent all the people from their home state.
Representatives represent people from their home districts.
A district is an area within a state. The Constitution says the district may contain no fewer than 30,000 people. In 1987 the average district had a population of 519,000. The people in a district are sometimes called a Representative's constituency. Within a constituency, there are different groups with different needs and opinions.