Microsoft Office may be the most popular productivity suite on the market, but it isn't your only option. OpenOffice is a free open-source alternative with similar applications to Microsoft Office, plus a few additional utilities.

There are no restrictions on OpenOffice's use, even for businesses. And getting to grips with the new software shouldn't be an issue - its interface is extremely similar to that of its Microsoft rival.

Core applications include: Writer, a word processor; Calc, a spreadsheet tool; Impress, a presentations program; Base, a database utility; and Draw, a vector package that can also handle basic 3D graphics.

OpenOffice is compatible with Office, particularly so up to Office 2003. Microsoft's substantial rewrite for the 2007 suite could cause some problems, although the same is true for users of earlier releases of Office itself.

Over the following pages, we look at ways in which you can improve OpenOffice compatibility with Microsoft documents. With a few tweaks, it's possible to seamlessly exchange Writer, Calc and Impress files with colleagues who use Microsoft Office.

We also concentrate on the advanced features within Calc. By using this app to create a comparison between the present value of leasing a car and buying it outright, you'll see it's no poor cousin to Excel.

And this is the real value of OpenOffice. Some 20 years of design means it's become an extremely sophisticated but also immensely usable collection of productivity tools.

Just because the suite is free, that doesn't mean it's inferior to Microsoft Office. If you're looking to upgrade your own applications, the open-source route could be the best way to go in these cash-strapped times.

Over the following pages, we'll help you improve OpenOffice's compatibility with other productivity suites and teach you how to perform complex calculations in Calc.

Improve OpenOffice's compatibility

1. Download and install OpenOffice 3.0. The suite works seamlessly with versions of Microsoft Office up to and including the 2003 release. It's also possible to use the software with Office 2007, but you may wish to tweak some settings first. Go to Tools, Options, Writer.

OpenOffice compatibility: Step 1

2. In the dialog box that pops up, click the plus sign next to Writer and select Compatibility. This dialog also provides options for compatibility with earlier versions of OpenOffice. Some settings, such as leading and word wrap, can provide unexpected results when working with Office files. These settings can be modified here.

OpenOffice compatibility: Step 2