The my_sales_summary.xlsx workbook file is open.
The C drive on your computer has been indexed.
It has dawned on you that you will be creating a large number of workbook files that will contain similar types of data and have similar file names. You decide to include key information in your workbook file, in the form of workbook properties, to make it easier for you to search through your workbook files. You also want to add a custom property so document recipients can easily tell if a workbook file is the approved, final copy.