What Is Display Advertising?
Display gets judged by search advertising's standards, which is why so many businesses conclude it does not work. This explains what it actually is, how the buying happens, what the industry's real problems are and when a modest budget is worth spending on it.
What Display Advertising Is
Visual adverts served on other people's websites, apps and video platforms rather than on a search results page. The banner beside an article, the box inside a weather app, the advert before a video.
The largest route into it. The Google Display Network.
A very large collection of sites and apps that have agreed to carry adverts, bookable through one account. For most small businesses this is the whole of display, because it is the only part they will ever touch directly.
The wider version. Programmatic exchanges.
The same kind of advertising space, sold across the rest of the web through automated marketplaces. Larger advertisers buy here. The mechanism is the same and the plumbing is more complicated.
What unites all of it. Interruption.
Nobody visited that page to see your advert. They came for the article, the weather or the video. Everything that makes display behave differently from search follows from that single fact.
How The Buying Actually Works
A page begins loading. In the time it takes to appear, an auction runs for the advertising space on it and a winner is chosen. This happens on every page load, millions of times a second across the web.
The publisher. The site with space to sell.
A newspaper, a recipe blog, a game. They make space available rather than selling it directly, because selling it directly to every advertiser would be impossible.
The advertiser. You, wanting to reach somebody.
You specify who you want to reach and what you will pay. You do not choose the individual page, which is the source of several problems later on this page.
The four pieces of plumbing. One sentence each.
An ad network collects publishers together and sells their space as a bundle. An ad exchange is the marketplace where that space is auctioned. A demand side platform is the tool advertisers use to bid. A supply side platform is the tool publishers use to sell.
Why this matters to a buyer. Distance.
Between your money and the advert appearing sit several companies, each taking a share. That is not necessarily wrong. It does explain why the amount reaching the publisher is smaller than the amount leaving you.
How Adverts Get Targeted
You are choosing who sees the advert rather than where it appears. These are the ways that choice gets expressed.
Contextual. Based on what the page is about. A bathroom fitter advertising on articles about bathroom renovation.
Audience. Based on interests or signals that somebody is in the market. A garden designer reaching people the platform believes are planning landscaping.
Demographic. Age, location, household characteristics. A retirement living developer reaching people over a certain age within twenty miles.
Remarketing. People who already visited your site. A kitchen showroom reaching everybody who viewed a range and did not enquire.
Custom segments. Built from what people have recently searched for. A roofer reaching people who searched for flat roof repair last week.
Placement. Named sites you choose yourself. A wedding photographer advertising on a specific regional venue directory.
Which of these is strongest. Almost always remarketing.
Reaching somebody who already showed interest costs less and converts better than reaching a stranger, which is why block eight returns to it.
Formats
The shape the advert takes. Each trades something for something else. The trade is worth understanding before a designer is briefed.
Responsive display. You supply images, headlines and text. The system assembles them to fit whatever space it wins.
Cheap to produce and it fits everywhere. The trade is control: you cannot know exactly how any given combination will look.
Fixed size banners. Designed to exact dimensions.
Complete control over appearance. More expensive, because several sizes are needed to cover the common spaces.
HTML5. Animated or interactive units.
More attention-getting and more expensive to build. Worth it where the product needs demonstrating rather than showing.
Native. Units styled to match the page they sit on.
Less obviously an advert, which improves attention. It has to be labelled as advertising. A unit that feels deceptive damages the brand it promotes.
Video, in stream and in app. Before or during other content.
The most expensive to produce and the most capable of explaining something. Suits considered purchases rather than impulse ones.
Display Compared With Search Advertising
These are not two versions of the same thing. They meet people at opposite ends of a decision. Almost every complaint about display comes from measuring one with the other's ruler.
Search meets somebody looking. The wanting already happened.
A person typed what they needed. The advert answers a question that was already asked, which is why a click is likely and why the space costs what it does.
Display interrupts somebody doing something else. No question was asked.
They were reading, watching or playing. Your advert asks them to stop, which most people will not do. That is entirely reasonable of them.
What follows for click rates. Expect far lower.
A display click rate compared against a search click rate will always look alarming. We quote no figures, because any benchmark without a named publisher and date is somebody's number repeated. The direction is the point: substantially lower, by design.
What follows for the path to sale. Expect it to be longer.
Somebody who sees an advert today may act in six weeks, having searched your name in between. Last click reporting gives that sale to search. Search did the closing rather than the introducing.
What to judge it on instead. Assisted conversions and brand search.
Whether display appeared anywhere in the paths that ended in a sale, plus whether people started searching your name more after it began.
How It Is Priced
Display is bought in one of two ways. Underneath both sits a standard that decides whether you got anything for the money.
Cost per thousand impressions. Paying to be shown.
You pay for the advert appearing, whether or not anybody acts. Suits awareness objectives, where being seen is the point.
Cost per click. Paying for the response.
You pay only when somebody clicks. Feels safer to a small advertiser. It quietly shifts the risk of poor creative onto you rather than away from you.
The standard underneath both. Viewability.
An advert counts as viewable when enough of it has been on screen for long enough for a person to have had the chance to see it. Adverts load below the fold, in tabs nobody looks at and on pages closed instantly.
Why this matters more than the pricing model. An unseen impression is worth nothing.
You can buy a great many impressions cheaply and have almost none of them appear on a screen. Ask any supplier what proportion of your impressions were viewable, then ask what standard they are using to say so.
The Problems Nobody Advertises
Display has real problems that the industry selling it rarely volunteers. Knowing them is what separates a buyer who can hold a supplier to account from one who cannot.
Banner blindness. People have learned not to look.
Decades of exposure have trained most of us to ignore the shapes and positions adverts occupy, frequently without registering that we did.
Ad blockers. A meaningful share of people never see display at all.
Click fraud. Automated traffic clicking adverts to generate revenue for whoever hosts them. Every sizing of this problem in circulation is contested, which is exactly why we quote none.
Made for advertising sites. Sites existing only to carry adverts, with content assembled to attract cheap traffic. Your budget can land there without anybody choosing it.
Brand safety. Your advert can appear next to content you would never associate with. You chose an audience rather than a page, which is the trade you made.
Budget leaking. Left broad, targeting spends money in places that will never produce anything, quietly and continuously.
The ground moving. Building audiences from cross-site tracking is being restricted, which changes what targeting can do.
When Display Is Worth Buying
Having set out the problems, the useful question is where display genuinely earns its place. There are clear answers in both directions.
Remarketing, almost always. The strongest use of a small budget.
Reaching people who already visited your site. They know who you are, they showed interest and the audience is small enough to be affordable. If a small business buys one kind of display, this is it.
Long consideration purchases. Where display has time to work.
Kitchens, extensions, vehicles, weddings, anything researched for weeks. Repeated presence during that period is exactly what display is built for.
Cold prospecting on a small budget. Usually the weakest use.
Reaching strangers at a scale small enough to be affordable is rarely enough to register with anybody. The budget spreads too thin to be remembered.
Who should not bother. Said plainly.
Emergency and urgent trades, where the customer is searching in the moment. Very local businesses with tiny catchments, where the wastage is severe. And any business whose website cannot yet convert the traffic it already has.
Judging Whether It Worked
Display reporting can be made to look excellent by anybody who wants it to. Knowing which figures flatter is the difference between a report and evidence.
View through conversions. Treat with care.
A sale credited because somebody was served your advert at some point, without clicking it. Sometimes the advert genuinely contributed. Sometimes the person was going to buy regardless and happened to load a page carrying your banner.
Assisted conversions. More reliable.
Sales where display appeared somewhere in the path. Still not proof of causation, though much closer to evidence than a view through.
Brand search lift. The strongest signal available.
Whether people started searching your name more after display began. Awareness advertising working looks like this. It is also hard to fake.
Would it have happened anyway. The question underneath all of it.
Remarketing reports beautifully because it targets people already interested. Some of them would have returned regardless, so ask what proportion. The full treatment is in return on marketing investment.
Common Mistakes
Each of these is a default left alone rather than a decision made badly, which is why they appear on so many accounts.
Leaving automatic placements unchecked. The system will find you cheap inventory. Cheap inventory is cheap for reasons.
No exclusion lists. Nothing preventing your adverts appearing on categories of site you would never choose. This takes an hour once.
No frequency cap. Nothing limiting how often one person sees the advert. Beyond a point, repetition stops persuading and starts irritating.
Judging on click rate alone. The measure display is worst at, used as the verdict on the whole channel.
Sending traffic to the home page. Somebody interested in one thing lands on a page about everything, then leaves.
Running it with no remarketing tag in place. The most avoidable one. Without it you cannot build the audience that makes display work, so you are buying the weakest version and skipping the strongest. The wider map is in what is digital marketing, the data question is in what is first party data. The full guide is on the digital marketing hub.
