When a bill or resolution is introduced in the House or Senate it is assigned a bill or resolution number, the text is printed, and it is assigned to a committee. Full text of bills and resolutions can be found online:
For bills and resolutions not available online:
If a committee votes favorably on a bill, it is "reported" from that committee to the full House or Senate. The bill is accompanied by an actual report, which explains the purpose of the bill, reviews past Congressional actions on the subject, specifies how the bill changes existing law and its expected effects on the federal budget and the national economy. Reports are identified by Congress and report number. Reports, along with Congressional documents, eventually get compiled into the Serial Set.