Docs, Google's online word processing application, has gotten a little bit more useful today. It now lets you import files from Microsoft Office 2007, including Word files in the .docx format and ...

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.