Question: what are the various types of committees (not the list of committees) how are they different

title: United States congressional committee
text: By 1906 , the Senate maintained 66 standing and select committees -- eight more committees than members of the majority party . The large number of committees and the manner of assigning their chairmanships suggests that many of them existed solely to provide office space in those days before the Senate acquired its first permanent office building , the Russell Senate Office Building . There were so many committees that freshman Senator Robert La Follette of Wisconsin was assigned chairmanship of the Committee to Investigate the Condition of the Potomac River Front at Washington . According to La Follette , he `` had immediate visions of cleaning up the whole Potomac River front . Then ( he ) found that in all its history , the committee had never had a bill referred to it for consideration , and had never held a meeting . '' In 1920 , the Congressional Directory listed nearly 80 committees , including the Committee on the Disposition of Useless Papers in the Executive Departments . By May 27 , 1920 , the Russell Senate Office Building had opened , and with all Senate members assigned private office space , the Senate quietly abolished 42 committees .