Files with the extension .xls - is a spreadsheet by using Microsoft Excel program, which is a widely used Microsoft Office software package.
Resolution .xls files are created by Microsoft Excel 2003 or earlier. Starting with version 2007 in Excel uses a different format - OOXML, and tables .xlsx files have permission.
Progenitor Excel, how many other spreadsheet editors served Visicalc program, developed by Software Arts in 1979. Total has sold about 700 thousand copies.
The first was released Excel 1985 anddesigned for Mac, version Wndows appeared three years later. Excel provides the user functions, which previously did not offer one. For example, the ability to change fonts and appearance of the table.
An interesting innovation was the "smart" conversionvalue table - updated values of the cells, which affected changes, while other editors recounted the entire table, which could take a long time.
In 1993, Excel has been integrated with Microsoft Word software, and Microsoft PowerPoint, which marked the beginning of Microsoft Office.
In addition to Microsoft Excel, there are a number of programs that can be used to open files with the extension .xls for viewing and editing.
Microsoft Excel Viewer - a free utility from the manufacturer Excel, allows you to view and print the table.
Microsoft Excel up to the 2003 version differs own binary format - BIFF. In 2008, the company posted a format specification, which took 349 pages.
OpenOffice - office suite similar to Microsoft, but freely distributed under the Apache license. The development at different times led Corporation
LibreOffice - also a free office suite. Part of the OpenOffice developers due to administrative disputes founded his own project, distributed under lizenziey GNU LGPL.
Gnumeric - spreadsheet editor, cross-platform, available under the GNU GPL, then there is a free software.
Kingsoft Office - a proprietary office suite, produced by Chinese developer Kingsoft. There is a free version for personal use programs.
Actively developing applications for viewing and editing Excel files for mobile OS - Android and iOS.
For instance, Calc XLS or Office HD can be installed on the Apple device. OfficeSuite, Docs To Go, Kingsoft Office - good options for the Android OS.