Just going from memory here, a loose interpretation could be... a control updates a recordset and a form will update a record. Tab out of a control, and the form's recordset gets updated. Navigate to a new record and the table's record get's saved.
Access_Novice,
what you are doing is the correct thing. You need to test the behavior. Understand what is going on behind the scenes. There will be times these nuances matter. The difficult part is remembering all of the nuances.
If you tab out of a control, it should be immediately reflected in the table. If you then navigate to a new record, it should be saved. The difference is, as I see it, you can still use the form's before update event before you navigate to another record to revert changes to the recordset.
With that I will include a link to an article on refresh. Bottom line, test the behavior. Testing your app before it goes live is a big deal and it is good you are asking these questions. I am just too tired right now to research a good descriptive and accurate answer.
http://msdn.microsoft.com/en-us/libr...ffice.11).aspx