Unlike television, where the 30-second commercial has been the go-to standard for decades, advertisers take a variety of approaches when pitching products and services in videos on the Web. Last May, the Interactive Advertising Bureau collaborated with more than 140 different online publishers, including Microsoft (MSFT), Google (GOOG), and Yahoo! (YHOO), to create a set of guidelines for the five most common formats. Some of the formats are not much different from ads you might see on television; others harness the interactivity of the Internet to engage viewers.
What: A 15- or 30-second ad that viewers watch before a show or video clip ("pre-roll"), at some point during the video ("mid-roll"), or afterward ("post-roll"). Sometimes, clicking on them can take viewers to another site.
Strengths: It's familiar turf to TV advertisers, who don't have to change much about their commercials to make them into pre-rolls for the Web. And because it's the most predominant format, an advertiser can place pre-rolls on a wide variety of sites and get back fairly robust data about who's watching them and where.
Weaknesses: It scares off impatient Web surfers, who tend to view video content in bite-size chunks. It also doesn't offer much of an opportunity for interactivity.
A site where it's used: MSN
An advertiser that uses it: IBM (IBM)
What: A pre-roll, mid-roll, or post-roll that offers viewers some form of interaction, such as entering a Zip Code or stock ticker, or playing a short game. The ad may persist for longer than 15 or 30 seconds if a viewer engages with it.
Strengths: It's highly customizable, leaves viewers with a strong memory of the brand, and sometimes collects more data about each viewer than a pre-roll would.
Weaknesses: It's not supported by a large number of Web publishers, and can also be seen as a needless distraction by viewers.
A site where it's used: Yahoo!
An advertiser that uses it: Esurance
What: A text or graphic that appears on the bottom or top portion of the video for a brief period while content is in progress. Typically, viewers can click on it to expand the ad or go to an advertiser's Web site.
Strengths: It doesn't interrupt the viewer's experience, and it's supported by a wide variety of Web publishers. Also, most TV viewers are accustomed to the format—it has become common practice for networks to promote their programs with overlays on television.
Weaknesses: Some viewers find overlays a disturbance, and sometimes they can't even tell that overlays are ads.
A site where it's used: YouTube
An advertiser that uses it: Electronic Arts (ERTS)
What: Similar to an overlay, but the message briefly appears alongside the actual video player rather than on top of it.
Strengths: It's not as intrusive as an overlay, and it can still be targeted to particular audiences and timed to appear at moments when viewers are most likely to click on it.
Weaknesses: Not supported by as many Web publishers as overlays, and it's easier for audiences to ignore.
A site where it's used: Yahoo!
An advertiser that uses it: Adobe Systems (ADBE)
What: A static banner that appears alongside a video player, typically in conjunction with another ad from the same sponsor, like a pre-roll or overlay.
Strengths: Companion ads give viewers a branded message for the duration of the video, and invite them to click through to the advertiser's site or expand a pop-up at their leisure.
Weaknesses: Because it's not standard for all video players to place companions alongside them, it's mostly used for customized campaigns.
A site where it's used: MySpace (NWS)
An advertiser that uses it: Hewlett-Packard (HPQ)
Douglas MacMillan is a staff writer for BusinessWeek in New York.