This MSAccess tutorial explains the purpose of a combo box in Access 2003 (with screenshots and step-by-step instructions).
A combo box is an object or control found on a Form in Microsoft Access. It is a drop-down list of values that the user can select from. You can set up the combo box to restrict the user's selection to the items in the list. Or you can allow the user to enter a value that is not contained in the list as well as select an item from the list.
Below is a combo box that has been set up to display a list of category names. This particular combo box displays only one column in the drop-down, but it is quite easy to change the combo box to display more than one column.
Here is what a combo box would look like if it displayed multiple columns. In this case, it also displays the column headings such as Company Name, Address, City, and Region.
Combo boxes generally serve the following purposes.
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