Controls are the parts of forms that most users see and work with. Controls can show data or accept data entry. They can perform calculations on data. They can display messages. They can also add visual effects, like lines or pictures, to make forms easier and more interesting to use.
Some controls are bound. A bound control is attached directly to a specific field in a selected table or query. The direct attachment means that a bound control can add, change, or display live data. (This lesson will discuss controls bound to fields in tables. To learn more about queries, see the course "Queries I: Get answers with queries.")
When someone enters or changes data in a bound form control, that new data or changed data immediately enters the table. Data viewed in a bound control will change in the form whenever it changes in the table.
Controls such as decorative lines and instructions are not bound to table data, because these controls stay the same. Calculated controls are not bound, because values that can be calculated do not need to be stored in a table.