A CSV (comma-separated values) file is a simple text file in which information is separated by commas, and is common in spreadsheet apps.

You can insert or generate the data for the CSV file in Microsoft Office Excel 2007 and then save the file in CSV format. CSV files outputted by Excel 2007 can be used in any program that can read ...

Select "CSV (Comma delimited) (*.csv)" from the list of potential file types. Choose the folder where you want to save the file from the small Explorer area at the top of the window.

If you've encountered a CSV file and you're unsure what they're for, the good news is they're pretty straightforward and easy-to-use with apps you already know.