Jargon Buster


Viewability is an online advertising metric that aims to determine only impressions that had the opportunity to be seen by users. For example, if an ad is loaded at the bottom of a webpage but a user doesn't scroll down far enough to see it, that impression would not be deemed viewable. Viewability is not a measure of ad effectiveness.

Viewable Impressions

A digital ad that had the opportunity to be seen, sometimes referred to through the traditional print media term of being “above the fold”. The current industry criteria for a standard ad unit to be considered viewable is that 50% of the canvas was within the consumer’s rendered window for a minimum of 1 second – the time required for a consumer to understand that the unit is a piece of advertising. Viewability is not a measure of ad effectiveness.

Virtual Reality (VR)

Virtual reality or virtual realities (VR), also known as immersive multimedia or computer-simulated reality, is a computer technology that replicates an environment, real or imagined, and simulates a user's physical presence and environment.

Voice search

A method to search by speaking, rather than typing which can save time on doing tasks or allow the user to multi task. Intelligent assistants such as Siri and Alexa offer voice activated search results. 


VPAID or ‘Video Player Ad-Serving Interface Definition’ establishes a common interface between video players and ad units, enabling a rich interactive instream ad experience. The two main areas that VPAID covers are providing consumers a rich ad experience and capturing ad playback and user interaction details. For more information about VPAID see here


A list of email addresses which an email-blocking programme (spam filter) will allow messages to be received from, or a list of websites that an advertiser will permit their ads to be placed on.

Your Online Choices (YOC)

This website provides consumers with information about how behavioural advertising works, further information about cookies and the steps they can take to protect their privacy on the internet. It is written by and supported by the internet advertising industry as part of an initiative to enhance transparency and control for online behavioural advertising. The UK version is at www.youronlinechoices.eu/uk.

Are we missing something?

If there is a term that you think is missing from our directory, we would love to hear from you. Submit a term and a definition and we will review it.