XLS files are Excel workbook files created in Excel 97 or Excel 2003. The 2007, 2010 and 2013 versions of the program use the XLSX format by default to save workbooks, but can also use the XLS format.
DBF (database) files, wildly popular with business PC owners in the 80s and 90s, have since been replaced by newer technologies. Luckily, if your company is still using DBFs, a few different software ...
How-To Geek on MSN
Don't underestimate the power of the $ sign in Excel formulas
Build more efficient spreadsheets by using the dollar sign to lock specific rows, columns, or permanent addresses when referencing cells.
Avoid Excel friction and save time by customizing the interface, shortcuts, highlights, and formula editing.
Some results have been hidden because they may be inaccessible to you
Show inaccessible results