Where is the best placement for a banner ad on a web page?

The top of the web page is the most sought after place for banner placement. Anywhere below the fold is less desirable because the page will load your banner ad costing you an impression, but it may never be seen. This does not mean that there are not some instances where banner advertising within the page is not effective.

One great placement is with an article, especially if the article meets your targeting requirements. The person reading the article is engaged with the page and their field of view stays in the area of the article for quite a while, making this a great area to place your ad.