The Change Log report allows you to find all changes made by any user during any time span.
Changed By - The user who made the change(s)
Date Changed - The range of dates to search for changes to the objects
Object Type - The type of object changed
Object ID - If you know the specific object you are looking for you can enter its ID to make sure to only report on that one object
Record ID - The ID of the Record that contains the object that was changed. All Records, Data, Documents, Record Note, Record Tracking, etc. are related to Records. If you enter that Record Type you can see all changes related to that specific Record.