roll call vote - A vote in which each Senator votes "yea" or "nay" as his or her name is called by the Clerk, so that the names of Senators voting on each side are recorded. Under the Constitution, a roll call vote must be held if demanded by one-fifth of a quorum of Senators present, a minimum of 11.
Congressional Sessions lists all Congresses and corresponding years - from 1789, when the 1st Congress met, through the current Congress.
You can access legislative information, by bill number or key words, from the THOMAS Web site. Information from the present back to the 93rd Congress (1973) is available on THOMAS.
For information on the Senate, Congress, the legislative process and the federal government, the Virtual Reference Desk is a good place to begin.