Since not all software has built-in parental controls or filters, it’s a good idea to install some parental control software to act as a nanny for everything your children do on the computer.
When choosing parental control software there are several features to look out for:
Age-specific settings - What's appropriate or inappropriate can depends on a child's age. A 15-year-old should be allowed access to a wider range of websites than, say, a 7-year-old. Good parental control software allows you to quickly set things up for your child's age.
Keyword filters - Many packages block or allow content based on keywords, and should be intelligent enough not to block websites which include an otherwise banned word in its URL. For example, a search for Middlesex might be deemed inappropriate by some packages.
Black- and white-lists - Some packages filter websites based on their category: drugs, pornography, weapons etc. They can also have blacklists (sites which are disallowed) and whitelists (a list of sites which are allowed). However, with the sheer number of new sites popping up, it's best to have a package that can intelligently process a list of search results and determine whether a particular site contains objectionable content or not.
Scheduling - Not only should you be able to specify which hours your child can use the computer (ideally you should be able to choose different times for each day) but also a limit on the total time per day. It should also be able to block internet browsing, or other specific applications at certain times to prevent kids being distracted by games, for example, when they're supposed to be doing their homework.
IM monitoring - If you allow your child to use an instant messaging service, parental control software should be able to monitor their conversation and prevent them sending personal details, such as their address, even to approved friends. Most IM clients aren't encrypted, so anyone could be 'listening' in on the conversation.
Application blocking - Not all parental control packages support this, but it's worth buying one that allows you to prevent certain applications from being used - ideally at certain times.
Remote management and alerts - The best software allows you to make changes to the PC running the parental control software from another computer. It should also send you alerts if, say, there was an attempt to visit a blocked website.
Finally, it should send you a detailed report so you can easily see what your child has been up to, how long they've used the computer before and more.
It's a good idea to explain to your child how the software works, and whether you're monitoring their every move or not, rather than doing it secretly, then scolding them when they do something you disapprove of.
Also bear in mind that parental control software isn't 100% infallible and isn't an excuse to leave your kids unsupervised when using the computer. It's ultimately your responsibility to ensure they stay safe, not a piece of software's. Older children will always find ways around such safety measures, including using USB flash drives acting as proxies to let them browse any website they like, so it can be beneficial to disable USB ports and DVD drives in the computer's BIOS for this reason.
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