The personal computer revolution is all about freedom of choice, but, ironically, software companies typically try to control what you do. You don’t buy their program; you license it. You can only use it on a specified number of computers. You can’t modify its source code.

As a reaction to this, the “open source” software movement came into existence in the late 1990s, with roots that go back to the hacker culture of the 1960s. Open-source software is developed and improved by users with programming skills who then share their efforts with anyone.

Open-source programs are typically free, although some carry fees and come with technical support. It’s a revolutionary concept in product development that’s based upon cooperation rather than competition. Open source positively smacks of socialist utopianism.

Should you or your business consider it?

Bernard Golden thinks so. He’s the author of the just published book Succeeding with Open Source (published by Addison-Wesley). The book is a how-to guide for organizations that want to move away from high-cost commercial software.

Golden is also CEO of Navica, Inc. (http://www.navicasoft.com), a consulting firm in San Carlos, Calif., that helps organizations migrate to open-source platforms. Depending on your time and talent, you may be able to do it yourself.

There are nearly 100,000 open-source products out there, though the better known ones include the operating system Linux (a replacement for Microsoft Windows), the browser Firefox (for Microsoft Internet Explorer), and the office suite OpenOffice (for Microsoft Office).

You’ve probably detected a trend here. Along with avoiding the high cost of popular commercial software, another benefit to open-source software is greater security. For years, hackers have gone after Microsoft products, and Microsoft’s security vulnerabilities are legion.

Of course, there are downsides to open source, and in a phone interview Golden pointed out the most important one: Ease of use is somewhat lacking. “Open-source programs are not quite as good with the ‘fit and finish,’“ he said. “Microsoft excels at offering wizards and so on that make it easier to get started with a product.”

Another downside is program availability. The situation here is similar to that with the Apple Macintosh computer. Despite the existence of many programs, if your needs are specialized, you may need to look elsewhere.

If you haven’t already dipped your toe in the water of open source, the easiest way these days is to download Firefox (http://www.mozilla.org/firefox). This free, fast, and intuitive browser is a direct descendent of the first graphical browser, Mosaic, and is gaining in popularity.

In the first 6 months after its release in November 2004, Firefox was downloaded an estimated 50 million times. This has caused the market share of Microsoft Internet Explorer, previously thought to have a monopoly on the market, to dip slightly.

Firefox has a sister e-mail program called Thunderbird, which is also free and open source. Along with e-mail, Thunderbird also handles Usenet newsgroups. And there’s a simple Web page creator called Nvu.

OpenOffice (http://www.openoffice.org) is a much larger program, but it is still easy enough to experiment with. It includes a word processor, a spreadsheet, a drawing program, and a presentation program. Versions exist for Windows, the Mac, and Linux in English as well as other languages.

Although it has millions of fans, Linux (http://www.linux.org) poses more technical challenges. It’s more difficult to install and learn than Windows (though once you do, it’s as easy to use, according to reports from those who use it). As testimony to how mainstream Linux has become, you can now buy a Linux-based computer at Wal-Mart.

Companies such as Red Hat, Inc. (http://www.redhat.com) place a user-friendly interface over Linux and add features and support, though pricing can approach that of some commercial software.

Organizations that currently pay significant licensing fees for commercial software stand to gain the most from open source. If you’re exploring the adoption of open-source programs for critical business functions, it can make sense to bring in outside expertise.

At Navica, said Golden, “We usually focus on identifying high-payback opportunities that will justify making the effort. After that, outlining any changes necessary in manual or automated work processes needs to be done. Implementation, testing, and transition follow.”

iRadeon.com (http://www.iradeon.com) is another consulting firm that specializes in helping businesses migrate to open source. This Roseville, Calif., company specializes in allowing companies to deploy and manage open source software to multiple locations over the Web.

For more on open source, check out the Open Source Initiative (http://www.opensource.org).