build an animated ad in photoshop cs4.
Universal ad sizes
The Interactive Advertising Bureau offers guidelines for ads to be viewable on most sites. While there are more than 15 sizes, four are considered universal.
Leaderboard: 728 pixels x 90 pixels — usually found stretching across the top of Web sites.
Medium rectangle: 300 x 250 — usually found in the side rail of a site next to content.
Rectangle: 180 x 150 — the small size allows it to appear in multiple places throughout a site.
Wide skyscraper: 160 x 600 — This vertical ad usually runs on the side of a site next to content.