The Site and Category Exclusion Tool allows advertisers to choose not to have their ads run on certain sites and is executed on a per campaign basis. At the site
level, users can exclude an entire domain, a sub-domain, or specific pages within it. Meanwhile, topic (or category) exclusion allows users to keep their ads from running against sexually suggestive,
profane, tragic, gory and other edgy or potentially conflicting content.
Advertisers also have the option to exclude particular types of Web pages. For example, they can keep their ads from running on social networking, video and image sharing, and error pages. There's also the option to block up to 20 IP addresses.