All ads use subtle animation to attract attention (without being too obtrusive) and also to allow the message to develop over a few seconds. This allows the ad to include more engaging textual and visual prompts, without this having to be crammed into a single image.
Under the hood, the ads were constructed in HTML5. Images and codebase are optimised to keep filesize low, so ads load fast. They don’t display until the rest of the page is ready (“polite loading”) and don’t animate unless they are on screen.
Each ad targets a defined customer profile who is looking to improve their English in the particular skill area offered by the related book. Because the ads were relevant and clear, the click-through rate was many times higher than the site average.