Glossary of Digital Advertising Terms

Sovrn Publisher Advocate // December 5, 2016

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There’s lots of lingo in digital advertising. Here we shed light on the terms so you can understand what the industry is talking about.

Ad Tag – A piece of code that sends a request for an ad to an ad server. The code is responsible for calling in the correctly sized creative and placing the ad in a  specific ad zone on a web page.

Ad Exchange – Exchanges are the marketplaces that publishers, advertisers and ad networks do business on. This is where data is processed and traded in order to set prices and serve an ad.

Creative – The actual advertisement that users see.

Ad Stack – This is the order that ad networks are called to fill an ad request. The network at the top of the stack will have the first chance to fill and if they don’t get a high enough bid then the request will be passed to the next network in the stack.

Price Floor – This is the minimum CPM a Publisher is willing to accept for an ad on their site. A price floor stops low bids from the top of the stack taking priority over higher bids from lower in the stack.

Demand Side Platform – A company that provides advertisers with a marketplace to purchase ad inventory.

Passback Tags -When an ad partner decides or is forced to not serve an ad impression, a passback tag is called that sends another ad request to another ad network.

Real-Time Bidding – RTB is what makes selling individual impressions on your site possible. Ad networks present your site and audience to advertisers and they make bids based on how valuable that impression is to them. This happens for each ad unit and takes mere milliseconds for advertisers to calculate the worth and place a bid.

Backfill – This is any inventory that has not been pre-sold. It can also be inventory that has been filled after an ad network passed on it.


Ways to Buy/Sell Ad Inventory

CPA – Cost-per-acquisition campaigns pay out whenever a visitor on your site interacts with an advertisement in a way that benefits the advertiser. These actions consist of registering via email, answering a question, or making a purchase after visiting the site through the advertisement. Essentially if a visitor does something that is valuable to the advertiser, you get paid.

CPC – Cost-per-click means you get paid when someone clicks an advertisement. The individual payouts for this are not as large as CPA but since all a visitor has to do is click, the Publisher gets paid much more frequently.

CPM – Cost-per-mille (thousand) has the smallest payout per individual ad served but it also pays the most consistently. Advertisers pay each time one of their advertisements is loaded on a webpage and this CPM measures how much you make for every thousand impressions. The formula is: (Cost to Advertisers/Impressions) * 1000 = Cost per Mille or cost per 1,000 (Impressions)

eCPM – This ad performance metric means the effective Cost-per-mille across your site.The formula is:  (Total Earnings/Total number of Impressions) * 1000 = effective Cost per Mille.

RPM – Revenue-per-mille is a metric used almost exclusively in Google Adsense. It is a measurement of your revenue per thousand impressions.

Fill Rate – This is the percentage of ad requests that were filled by each network. The formula is: (Filled Impressions/Requested Impressions) * 100  = percentage of your requests that are filled by sovrn.

Programmatic Advertising – Programmatic is an automated way of buying and selling ad inventory. Ad inventory is put on the market (called an exchange) and made available to advertisers for purchase.


Ad Types/Sizes

Ad Units – Ad units are the advertisements shown on a website. They are typically located around the perimeter of the page in order to be less obtrusive and are sized according to industry standards. Ad units are the advertising inventory publishers sell to advertisers.

Standard Ad unit sizes

    • Banner/Leaderboard (728px x 90px)
    • Rectangle (300px x 250px)
    • Skyscraper (160px x 600px)

Native Ads – Ads that look like they are a part of the website and do not take away from the user experience.

IBV – In-banner video is a form of display advertising that automatically plays a video instead of an image and pays a much higher CPM (rate at which advertiser is willing to pay for every 1,000 impressions)


User Behavior

Ad impression – An impression is when an individual ad is served to a single user. If a page contains 3 ad units, there is the potential for 3 ad impressions every time a user visits the page.

Bounce Rate – The percentage of users who visit a page and then shortly leave without going to another part of the site.

Page View – A page view is registered whenever a website loads for a user.

Unique user – The first time a visitor goes on a website in a set period of time.

Visitor – Visitors are counted whenever someone visits a site regardless if they have been on before.


Header Bidding

Bidder – a bidder is simply a partner that is equipped to receive requests and send bids via a header bidding implementation. This could be a supply-side platform (SSP), ad network, retargeted, etc. There are now over twenty different ad tech companies that have their own “bidder.” It is best practice to work with at least 6-8 different bidders in a healthy header auction in order to increase competition for inventory.

Header bidding wrapper or container – A piece of Javascript that “wraps” together ad requests and bids in the <head></head> section of a website. Within 500-1000 milliseconds, the container sorts these bids and selects the winner. The wrapper organizes all partner bids and applies auction logic and key values to returns bids.

Header bidding mediation – Mediation is the main job of the wrapper or container code. The wrapper code asynchronously calls all bidders, collects their bids and determines a winning bid before the ad server ever gets involved (thus the terms “pre-bidding” or “advance bidding”, early terms used for header bidding).

Header bidding adaptor – Partner-specific code that allows them to communicate with the wrapper to receive requests and return bids to the auction.

Timeout – Header auctions must be completed within a very small window so they do not negatively impact page latency. Most wrappers, most notably Prebid.js, have timeout settings that allow a publisher to determine how long the auction should wait for each partner to return a bid before closing the auction.

Ad server – The winning bids from header bidding auctions are sent along to the publisher’s ad server  to select the appropriate line item and return the winning creative to the correct zone on the page. For most publishers using DFP, the winning bid must also compete against AdX dynamic allocation at that time.

Key values – When bids are received, the wrapper code adds the price and creative identifier to the ad server’s call as a set of query string parameters. This process is called key value targeting.

Header bidding line items – Line items are setup to target specific bid prices, allowing the bidders’ programmatic demand to compete with other line items based on price. The winning bid is then matched to the corresponding line item in order to select the correct creative to return to the page.

Ad creative – The actual ad asset (an image file) that is returned to the page which extracts and displays the ad from the bids returned via the header code.



Viewability – An online advertising metric focused on tracking ad impressions that are viewable by the user.

Viewable impressions – Viewable impressions take into account two variables: pixel area and duration. As defined by the Media Rating Council, a desktop display ad is considered viewable if 50% of its pixels are in view for a minimum of one second and 50% at a minimum of two seconds for desktop video. Both factors are dependent on the user’s behavior on that particular web page and are not an indicator of ad performance.

ATF/BTF – “Above The Fold” and “Below The Fold” refer to the placement of ad zones on a website. ATF means that the ad space is in the top half of the website and the user won’t have to scroll to view it. Below the fold means the ad is located near the bottom of the page. The value of ATF ad spaces is higher since it is almost guaranteed that a visitor will see it.

InView – Ads that only load when greater than 51% in view.

Viewable Engaged Time (Signal) – A user engagement metric that enables publishers to sell inventory on their website based on user engagement rather than impressions alone.

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