For example, two of the predecessor networks to the Internet, ARPANET and NSFNet, had "acceptable use policies" that banned network "use for commercial activities by for-profit institutions".
The first widely publicized example of online advertising was conducted via electronic mail.
A floating ad, or overlay ad, is a type of rich media advertisement that appears superimposed over the requested website's content.
Floating ads may disappear or become less obtrusive after a preset time period.
More recently, companies have sought to merge their advertising messages into editorial content or valuable services.