Banners are an essential tool in your promotion program. It is is used on traffic programs as well as on banner exchanges. They can be placed in a number of advertsising situations. You should have several banners.

Banners are also used when you promote affiliate programs. Used correctly they can be profitable.

The trick using banners on your website is to use them sparingly. Overuse of banners makes you a banner farm. If there is no content on any page, just ads, your ranking will drop like a bomb.