Broadly this term refers to selling the right things to the right customer at the right time for the right price to maximize revenue. In online advertising it generally refers to maximizing the revenue of publishers and their impressions using tools such as price floors.

Mediation that takes place over the Web. Web mediation involves trafficking an ad network’s tags. The tags are called when the seller ranks the networks proxy bid higher than any other demand. If the buyer doesn’t take the impression a passback tag set up by the seller informs the ad network to go to the next highest bidder or ad network.

Trigger your campaigns based on actual or forecasted weather conditions

Video Player Ad-Serving Interface Definition. VAST supports relatively simple in-stream video ad formats that are not executable. VPAID was created to support more interactive rich media video formats. For more information see the Interactive Advertising Bureau (IAB) VPAID documentation.

Video Multiple Ad Playlist (VMAP) specification. This is an XML template that video content owners can use to describe the structure for ad inventory insertion when they don’t control the video player or the content distribution outlet.

A measure of whether an ad has been seen by a given user. Viewability measurement is achieved using javascript embedded within each creative which is then called for each individual ad impression. The script launches automatically as the page loads and immediately starts measuring if and when the creative is viewable based on a variety of measures. These may include whether a web or browser tab is in focus whether a particular ad is in view of a user based on where on the page the user has scrolled to how long an ad was visible based on these metrics and other factors. The most commonly used bidding strategy based on viewability is CPVM. In 2015 the Interactive Advertising Bureau (IAB) released industry standards for viewability. To learn more see the IAB website.

A quartile is 1/4th of something. Media players fire a series of engagement pixels as the video continues to play. These pixels typically indicate how many quartiles of a video has been played firing at 25% 50% 75% and 100% completion.

In online advertising a vendor generally refers to a company with a specific product or service such as creating or delivering rich media maintaining a CDN or providing third-party data.

Video Ad Serving Template. This is an XML-based video ad serving protocol. It was created to provide a uniform way for video content to be transferred from ad servers to video players on web pages. For details see the Interactive Advertising Bureau (IAB) VAST documentation.

See unique user ID.

Content on a website that was posted by users and not a centralized publisher. This includes social media posts as well as blogs wikis podcasting images videos audio files and other forms of media created and posted by users of an online system or service. Some sites support user content through advertising. Others are supported by donations subscription fees or a combination of methods. Examples of sites that emphasize or are built around user-generated content include Tumblr Facebook Twitter Instagram Pinterest Wikipedia YouTube Vine and SoundCloud.

A pixel used to synchronize user IDs assigned by different parties during an auction generally to apply frequency recency and other decisioning data. See also user ID mapping.

Each buyer and seller may assign their own different IDs to a user. Without knowing that Seller S's user ABC is the same as Buyer B's user 1234 it is impossible for B to value an impression from S. To allow for attribution and valuation different parties must synchronize their IDs by mapping one ID to another.

See unique user ID.

A place where data about a user is stored. In online advertising this often refers to a user's browser cookie. Sometimes certain user data may be stored server-side for a limited period of time. This data is periodically expunged from server records in order to prevent it from drastically slowing server function and does not contain personally identifiable information (PII).