A crucial factor in “keeping your audience” is the time they have to wait before the page is fully downloaded. Recent research suggests that the maximum time before boredom and impatience sets in is around ten seconds — by which time the main message or the bulk of your information should be on display. Of course, this time is affected by the speed of your Internet connection and the response time of the server, but keeping things small is generally a good policy.

There are a few tricks that can be used to reduce download times. For example, when adding graphics, specify the height and width of your image as attributes; this will help the browser to construct the page layout before the image has downloaded. Graphics should be kept small—try high-compression JPEG or PNG images for photographs, or reducing the complexity and number of colours in cartoon-style GIF images.