Ad Unit Style

The setup of the Google AdSense programs have made a diverse selection of different ad unit sizes and styles, as well as the link units and search units. AdSense for content unit styles include:

Horizontal Ad Units:

  • 728x90 Leaderboard
  • 468x60 Banner
  • 234x60 Half Banner

Verical Ad Units:

  • 120x600 Skyscraper
  • 160x600 Wide Skyscraper
  • 120x240 Vertical Banner

Square Ad Units:

  • 336x280 Large Rectangle
  • 300x250 Medium Rectangle
  • 250x250 Square
  • 200x200 Small Square
  • 180x150 Small Rectangle
  • 125x125 Button

Horizontal Text Link Units:

  • 728x15 -- 4 or 5 Links/Unit
  • 468x15 -- 4 or 5 Links/Unit

Square Text Link Units:

  • 200x90 -- 4 or 5 Links/Unit
  • 180x90 -- 4 or 5 Links/Unit
  • 160x90 -- 4 or 5 Links/Unit
  • 120x90 -- 4 or 5 Links/Unit
The Leaderboard and Banner ad options are obviously the best choices for page headers and footers. Leaderboards are more favorable since they are able to show more ads. Banners are the classic web format, and may come in handy when you're restricted by the available width of your web page.

Skyscrapers work excellently for advertisements, because they seem to be less affected by ad blindness than horizontal ad formats.
Rectangles, Squares, and Buttons are extremely convenient for placement inside a content area. It's true that the rectangles may be more difficult to place how you would like them to be, but they do offer some of the highest revenue potential.