What is display advertising?
Display advertising is the family of ads that sit on a page rather than in a search result or a social feed: the banner across the top of a news site, the square unit beside an article, the full-screen interstitial in an app, the video that plays before a clip. They are bought through ad networks and exchanges, most of the volume programmatically, and targeted by who the viewer seems to be, what they are reading, and what they did on your site last week.
Display was the first form of online advertising and it is still one of the largest by volume. It has also had to earn back its reputation: the banner ad taught a generation to look past the right-hand column, and the discipline has spent twenty years getting smarter about where, when and to whom an ad is worth showing.
Why it matters
Why display advertising matters
Because it is reach you can aim. Display puts a brand in front of a chosen audience at a scale and a cost that few other channels match, across the open web rather than inside one platform's walls. It is the workhorse of awareness for a launch, and it is the mechanism behind retargeting, where a person who visited the site is reminded of the product on the next ten pages they read. For a visual brand, display is also one of the few places online where the picture, not the copy, does the work.
It matters more for what it feeds than what it closes. Few people click a banner and buy. Many people see a brand ten times on pages they trust and then search for it, and display is where that familiarity gets built.
In practice
How display advertising works in practice
- 01
The brand or its agency decides who to reach and where, then buys the inventory: directly from a publisher for a premium placement, or through programmatic platforms that bid for impressions in real time against the audience data. The creative is produced in the standard sizes (a leaderboard, a medium rectangle, a mobile banner, a vertical) and often as a responsive set that the platform assembles from the pieces. Each unit has to say one thing in a glance and carry the brand's look without a second of attention to spare.
- 02
Then the campaign is read and tuned. Viewability (was the ad actually on screen), click-through rate, and the conversions that follow, whether from a click or from a later visit, tell the team which placements, audiences and creative deserve more spend. Frequency is capped so the same person does not see the same unit forty times, and the creative is refreshed before it goes stale.
Watch out
What people get wrong about display advertising
Judging it by clicks. Display's click rates are tiny and always have been, and a team that optimizes for them ends up buying the cheapest, worst placements. Measure it by the lift in search, direct traffic and conversions among the people who saw it. The other mistake is designing the unit last. A banner built from a cropped poster with the headline squeezed to fit is the ad people learned to ignore. Display creative deserves its own layout, drawn for the size it will run at.
