The United States Constitution created a new government for the United States with three separate branches with unique responsibilities. The legislative branch makes the laws for the federal government. The framers of the Constitution created a bicameral Congress, similar to Britain’s Parliament, but the two houses were created for a different reason in America.
The House of Representatives is based on population; the more people that live in a state, the more Representatives they get. Representatives serve two-year terms. The other house is called the Senate and it has equal representation: two from each state. The Senate was given the more important jobs in the Constitution and its members serve six-year terms.
To create a law, a bill–or proposed law–is brought up in the House of Representatives. Because of the number of suggested laws, all bills have to make it through Congressional committees before they are considered by the House. If the bill makes it out of committee, then it gets debated on the floor of the House and eventually gets voted on. If it passes, meaning a majority of the Representatives vote for it, the bill gets sent to the Senate.
The same process takes place in the Senate. The bill must go through committee, then get discussed on the floor of the Senate and must get over 50% of the Senators to vote for it. But the bill still isn’t a law yet because of the system of checks and balances.
The bill then goes to the President of the United States. The President can choose to sign it, making it a law, or veto it. When it gets vetoed, Congress has an opportunity to override a Presidential veto if they can get 2/3 of the House and the Senate to vote for it, but this rarely happens.
Sometimes a bad law makes it through this process. The Supreme Court, using the power of judicial review, can strike down the laws for being unconstitutional if they get brought before them. This often happens far later than when the laws was originally enacted.