After defining page layouts, assign which page layouts users see. A user’s profile determines which page layout he or she sees. In addition, if your organization is using record types for a particular tab, the combination of the user’s profile and the record type determine which page layout is displayed.
You can assign page layouts from:
1. The object’s customize page layout or record type page
2. The enhanced profile user interface.
3. The original profile user interface

Standard Object:

Custom Object: