While Google's contextual mechanism generally does a pretty good job of matching your site with the right kind of ads, the fact that it does sift through content in order to do so means things can sometimes go wrong. If you've repeatedly raved about luxurious en-suites in your fine hotels guide, for example, it's not too surprising if you're served an unwanted ad for bathroom installation. But how can you help prevent this happening?

The answer is actually pretty simple.

Using special comment tags in the html code you can designate areas of a page that you'd like Google to focus on in its search for keywords:

<!– google_ad_section_start –>
<!– google_ad_section_end –>

These are wrapped around the appropriate content in the usual way. So if, for example, you felt that the following text was likely to generate efficient delivery of ads to your site:

<p>LondonCity aims to bring you the best and latest info on London theatres and clubs, food and drink, pubs, bars and restaurants and dozens of other ways to enjoy the capital! </p>

both the starting and ending comments would be typed or pasted around it like so:

<!– google_ad_section_start –>

<p>LondonCity aims to bring you the best and latest info on London theatres and clubs, pubs, bars and restaurants and dozens of other ways to enjoy the capital! </p>

<!– google_ad_section_end –>

To isolate text that you don't want included in a keyword analysis, just add an 'ignore' option to the start comment only:

<!– google_ad_section_start(weight=ignore) –>

LondonCity would like to apologize to the Cats, Dogs and Small Mammals Association for wrongly claiming that their premises is open to the general public.

<!– google_ad_section_end –>

 

If you're fairly confident with code - and let's face it, most publishers cut and paste it quite regularly - using this option isn't hard at all, and a great way to add an extra boost to the relevance of your ads.