confusion with the sqlserver driver classname

sqlserver 2005 jdbc driver:sqljdbc.jar

driver class name : com.microsoft.sqlserver.jdbc.SQLServerDriver

sqlserver 2000 jdbc driver:msbase.jar,mssqlserver.jar,msutil.jar

driver class name : com.microsoft.jdbc.sqlserver.SQLServerDriver
Often people get confused with the driver class name and the driver to be used.The best approach I follow is to open the jar[say sqljdbc.jar] with a winzip[or equivalent] and observe the path.