Statutes are the written law as passed by the legislature (as contrasted with case law and common law, developed by the courts).
Bills are proposed laws that are presented to the legislature for discussion and vote.
The Congressional Research Service is a public policy research department of the U.S. Congress. The department issues non-partisan reports for members of Congress to support the decision-making process. These reports can assist legal researchers in understanding the background and context of bills and laws. The reports are available from several web sites: