Congress is responsible for passing all laws that govern the country, including laws related to taxation, national defense, immigration, and many other areas. It also has the power to impeach the President, Vice President, and other high government officials.
The process of passing a law in Congress begins with the introduction of a bill in either the Senate or the House of Representatives. If the bill passes both chambers, it goes to the President, who can sign it into law, veto it, or allow it to become law without his signature.