Much is still not known about its effectiveness as a media. The most used form of advertisement, the banner ad, has lost much of its effectiveness. The competition for the advertiser's dollar is intense because of the 1,000's of sites hoping to finance their existance with web advertising income. The web advertising market has not been tapped by a good product. Clicking on a banner takes the viewer to the advertiser's website.
Banners can be static or animated.
Animated banners take longer to load and move rapidly on the screen. Many advertising banners are loaded from another site. Little symbol on listing points to an ad. Ad will be seen only if the viewer decides to click on the button. Most ads can only be viewed one at a time.