A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
You can merge cells, and also center text across several cells. This is often used to create titles or headings at the top of a worksheet.
See for example http://thenewpaperclip.com/2008/04/14/merge-and-center-in-excel-2007/ andhttp://thenewpaperclip.com/2008/04/15/center-across-selection-the-merge-and-center-alternative-in-excel-2007/.