So, you don’t have Microsoft Excel? No problem, you can download a free compatible version called OpenOffice Calc.
It will use most of the functions as per the Excel Help guides.
You can search for reviews of Open Office in Google, Yahoo, or other search engines, to gain an understanding of the product prior to downloading it.
It’s a great product that is free, and it will get you started with using spreadsheets, with out the expense of purchasing Microsoft Office.