Final answer:
A conference committee is formed to reconcile differences between the House and Senate versions of a bill to create a unified version that can be voted on again by both chambers before it goes to the President.
Step-by-step explanation:
If a bill passes both chambers of Congress but the versions are not identical, the next step is to form a conference committee. This is a temporary panel that is specifically created to reconcile differences between the House and Senate versions of a bill. Members of this committee, usually senior members from the original standing committees from each chamber, negotiate a compromise that both the House and Senate can accept without further amendments. This reconciled bill, often referred to as a conference report, then goes back to each chamber for a final vote. Once approved, it can proceed to the President's desk for signature or veto.