Change: The difference between the current price and the price of the previous day of a security.

Commission: A service charge assessed by a broker and his/her investment company in return for arranging the purchase or sale of a security.

Exchange: An area where an asset, option, future, stock or derivative is bought and sold.

SEC: The Securities and Exchange Commission. The SEC is an agency of the federal government which is in charge of monitoring and regulating the securities industry.