Answer:
''the House and Senate frequently pass different versions of the same bill''
Conference Committees are joint committees between members of the House of Representatives and Members of the Senate. The purpose of these workgroups is to resolve disagreements over Bills, as it is common for a Bill passed by the House of Representatives to be subject to amendments by the Senate. Conference Committees produce a "compromise bill" which both houses have to pass in order for it to go to the President.
