PCs and Macs have parental controls built into their operating systems, and each of their newest systems (Windows Vista and Mac's Leopard) offers parents more control than ever, says Ismael Matos of Geek Squad, a technology-support company. If you're considering upgrading your operating system, that switch might save you the cost of additional monitoring software.
To use your computer's controls, first set up individual user accounts for each of your kids. Check your computer's user guide if you're not sure how to do this.
Mac users: Next, choose System Preferences on the Apple menu, and click on Accounts. For each child's account, click on Parental Controls and you'll be given a list of categories (Mail, Safari, etc.) that you can restrict or monitor.
If you're running Leopard, Matos says, you can record IM conversations and designate with whom the child can talk via e-mail or iChat, among other things. You can also limit screen time. For instance, you can set the computer to automatically log your kids out at 8 p.m.
Windows users: The parental controls are accessed through the Control Panel. Look for User Accounts and Family Safety Control Panel. With Windows Vista, you'll be given choices about web restrictions and also have the option of receiving reports on your child's use of the computer. You can designate certain hours off-limits and block objectionable video games and programs.
No matter which system you have, most browsers (Safari, Firefox, etc.) have an automatic history log that shows which sites have been visited. Check your user manual to learn how to check the history, if you're not familiar with it. Make sure to check all the browsers on your computer if you have more than one. And be warned: Kids can learn how to delete the history to cover their tracks, so ask questions if you discover that the history was cleared by someone other than you.
Need more help? Both Apple (Macs) and Microsoft (Windows) have online tutorials and detailed info on their websites -- just Google "parental controls" and "Apple" or "Microsoft" to find them. Mac users can also make an appointment at an Apple store if there's one nearby. Or you can call 800-Geek-Squad for a phone consultation or to schedule a visit (it's pricey, though -- home visits start at $99).
With most issues of safety -- climbing a tree, riding a bike, crossing the street -- we progressively give kids more freedom. But in the digital world, new and different risks come up as they grow. Your instinct might be to back off as they approach the tween years, but that's when to get even more involved. And when they hit you with that tried-and-true "but all my friends are doing it" cry, compare notes with other parents; you'll probably find out that most are just as concerned (plus, you'll see which ones let their kids have unrestricted Internet access!).
Keep in mind that any protection you give your kids will, of course, be incomplete. The world is out there in all its beauty and ugliness, and some of that will come through the modem no matter what. Just don't throw up your hands and give up. Says Cynthia Edwards, Ph.D., a professor of psychology at Meredith College in Raleigh, NC: "Start the conversation early, and keep the conversation going."