It depends on how you want to use the software, and what skill level you'll be satisfied with. Unlike computer chess programs, which programmers have been perfecting for more than 30 years, bridge software development is still in relative infancy. The marketers' claims aside, no program yet bids and plays like a human expert. Still, there's no doubt that today's programs are improving, and many are worth owning for their teaching and entertainment value. Many programs have comprehensive online lessons that you can use to teach yourself, even if you know absolutely nothing about bridge when you start.
More experienced players use the programs for practice, too, especially for declarer play.
Doing your research Before you buy, check out Jim Loy's Software Reviews , a comprehensive page of descriptions, features and skill ratings for dozens of shareware and commercial bridge programs. Decide what you want your program to do and compare the features of Loy's top-rated programs. Then narrow your search to those best matched to your skill level. More advanced players may want to base their decision more heavily on the program's defensive skill rating, number of systems and conventions it plays, and the variety of deal options it offers. Most commercial software packages have web sites where you can get more details on each program's features and, in some cases, download a trial demo.