Most filters currently act simply as content filters. Software companies are now working to add privacy preferences to their content filters. In the future, label-reading software could enable consumers to set their computers to access only those Internet sites whose privacy policies match their privacy preferences.
Content screening software uses either a filtering or rating method.
Typically, the software recognizes a database of banned sites and search words. The database, however, requires regular updating, which may be at a cost to users through subscriptions. This design is not foolproof. It does not prevent a user from clicking on a link to a site that is not in the database, and it cannot stop a clever search that avoids the search words listed in the database. The rating method blocks access to sites that do not bear a particular rating.