What is display advertising? It is paid advertising that uses image, video or text ads on websites and apps, most commonly images such as banners. Whether it fits a campaign depends on the goal: reach and awareness, or conversions.
Readers new to the machinery behind these ads can start with what is ad tech and return here for the format itself.
How a display ad reaches a screen
Display advertising works by placing a creative in a slot on a publisher’s page or app, then choosing which user sees it. Industry glossaries describe it as image, video or text ads on websites, with image ads the most common. Marin Software defines the same family as online advertising using images, videos or text on websites and apps.
The delivery chain follows a recognisable order:
- The advertiser prepares creative. The ad is built as an image, video or text unit to fit a publisher’s slot.
- A pixel identifies the visitor. According to Marin Software, a pixel allows the ad server to identify the user and track their activity across different sites.
- The ad server chooses the ad. The same source notes that display ads are typically served by a third party based on the previous behaviour of the user.
- The ad appears in its slot. That slot may be a sidebar, a header or footer, or a place around a video.
The practical consequence is that a display ad is usually matched to a person’s earlier behaviour rather than to a request typed at that moment. That one fact explains most of the differences from search covered below.
Banner ads and standard ad units
A banner ad is the best-known display format. Marin Software describes banner ads as static or animated images that usually appear in the sidebars or the header and footer of a page. Banners sit alongside other formats in the same family, including interstitials, native ads and in-stream video ads, which show before, during or after a video.
IAB standard sizes
Sizes are standardised so one creative can run across many publishers. The IAB’s newer display package added larger, more immersive units alongside the older ones. These are the units named in its 2012 release.
| Unit | Size (pixels) | Planning use |
|---|---|---|
| Billboard | 970×250 | A wide, tall unit for campaigns that need a prominent page presence. |
| Pushdown | 970×90 | A wide, shallow unit suited to header-style placements. |
| Filmstrip | 300×600 | A tall unit suited to sidebar-style placements. |
The sizes come from MarTech’s report on the IAB release, and the portfolio itself is described by IAB Canada’s global standard ad guidelines.
IAB Canada says its New Standard Ad Unit Portfolio is made up of display ads, native ads and new media experiences. It describes the ads as lightweight, cross-screen and flexible in size, implementing LEAN principles. The emphasis is on better user experience, faster load performance and non-disruptive formats. For a media planner, that means checking that creative files stay light and that units suit mobile screens as well as desktop.
The IAB also published research on the new units. Eye tracking showed users viewed Rising Star ads 31% longer than standard formats, and consumers were 2.5% more likely to interact with a Rising Stars unit than with standard units. These are IAB-reported results for its own new units, not guarantees for any given campaign. They do suggest that larger formats are worth testing against the smaller defaults.
How display ads are bought and sold
Display inventory is sold through programmatic channels, direct buys or affiliate and CPA arrangements. A display advertising glossary describes a direct buy as reaching out directly to the publisher. Programmatic advertising is the automated alternative, where buying runs through technology platforms and the ad server decides which ad appears.
The route chosen shapes how much control the advertiser keeps over placement. Direct buys suit a campaign tied to a particular publisher’s audience. Programmatic buying suits a campaign that follows audience behaviour across many sites. Whichever route is used, confirming that impressions reach real people is a separate discipline, explained in what is ad fraud.
Pricing models: CPM and CPC
Marin Software frames the choice of pricing model as a matter of goals. For quickly reaching a large audience and building brand awareness, CPM is the better fit. For driving conversions and sales, CPC may be the better choice. The same guide adds that CPM is less effective for driving conversions, so a campaign that is judged on sales should not be bought purely on impressions.
Display versus search advertising
Display and search differ mainly in the moment of contact. A search ad answers a query the user has just typed, so it meets stated intent. A display ad appears while a person is reading, watching or using an app, and it is typically selected from previous behaviour. Display therefore tends to introduce or remind, where search tends to respond.
- Intent. Search starts from a request. Display starts from a behavioural signal or the content around the slot.
- Format. Display uses images, video or text units in set sizes. This makes creative production and size compliance part of the job.
- Buying. Display can be bought directly from a publisher or through programmatic channels, and can be priced by CPM or CPC.
- Typical role. Display builds awareness and supports remarketing. Search is the usual place to capture people already looking.
Many campaigns use both: display to create awareness, search to capture the interest it generates. Choosing between them is a question of where the audience is in its decision, not of one format being generally better.
When display advertising suits a campaign goal
Display suits campaigns that need visibility, repeated exposure or follow-up with people who have already shown interest. The supported reasons are specific:
- Reach and awareness. CPM buying favours quickly reaching a large audience and building brand awareness.
- Conversion goals. If sales are the target, CPC pricing may fit better than CPM.
- Remarketing. Marin Software notes that display ads allow remarketing opportunities, and a separate guide answers what is retargeting and how it builds on that.
There is one practical limit to plan around. The same guide points out that display ads can be blocked by ad blockers, so some of the intended audience may never see an impression. Treat reported reach as an upper bound for the people who could have seen the ad, and weigh that when a campaign depends on exposure alone.
Producing banner creative
Display creative is built to fit each unit size, so the same message is usually adapted for several slots. Because the IAB stresses faster load performance, a designer should keep files lean as well as visually clear. A tall Filmstrip and a wide Billboard need different layouts, so copy and imagery are reworked for each unit rather than stretched.
Format choice also changes the production brief. A static or animated banner needs only an image treatment, while in-stream video requires footage that works before, during or after another video. Native ads and interstitials bring their own layout constraints. Agreeing the formats and sizes first keeps production aligned with the placements the buying plan actually secures.
Frequently asked questions
Is a banner ad the same as display advertising?
No. A banner ad is one format within display advertising. Display also covers interstitials, native ads and in-stream video ads, according to Marin Software.
Do display ads appear only on websites?
No. They run on websites and apps, and may use images, videos or text.
How often does the IAB introduce new standard ad units?
Rarely. The 2012 release was the first new standard portfolio since 2003, according to MarTech’s report.
