Microsoft Excel (full name Microsoft Office Excel) is a spreadsheet-application written and distributed by Microsoft for Microsoft Windows and Mac OS X. It features calculation, graphing tools, pivot tables and a macro programming language called VBA (Visual Basic for Applications). It has been the most widely used spreadsheet application available for these platforms since version 5 in 1993. Excel is part of Microsoft Office.
This is the Special Upgrade version, although it does not appear like it actually does any verification for previous versions - instead, it relies on the retailer. This one is also in the original shrinkwrap.