These finishes most often referred to as urethanes or polyurethane's remain on the surface of the wood and form a protective coating. They are generally available in high-gloss, semi-gloss, satin and matte.
So, as you can see, the difference between Congress and Senate is quite simple. Congress is the legislative branch of the government. It has two parts; the Senate and the House of Representatives. So, the Senate is a part of the congress.
U.S. Senate, United States Senate, US Senate, Senate - the upper house of the United States Congress. House of Representatives, U.S. House, U.S. House of Representatives, United States House of Representatives, US House, US House of Representatives - the lower legislative house of the United States Congress.