CTV: Key definitions for the industry

Posted on Friday 26 August 2022 | IAB UK

Working in partnership with our connected TV (CTV) members and IAB Europe, we’ve developed a set of shared definitions for the CTV sector

One of the fundamental steps a maturing channel needs to take is to establish a shared understanding of key terms, in order to ensure that everyone across the supply chain is speaking the same language. We have developed the below definitions in partnership with our CTV members and IAB Europe, with the aim that they are used across markets. 


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Connected TV (CTV)

On Demand

Buying & Selling




Over-the-top (OTT)

Over-the-top media service encompasses all linear TV or video-on-demand (VOD), including advertising supported video-on-demand (AVOD), broadcaster video-on-demand (BVOD), and streaming content providers (such as Netflix, Amazon Prime, PlutoTV, etc.). These content providers distribute directly to viewers via the internet - bypassing the cable, broadcast or satellite platforms. OTT includes all devices (mobile, desktop, consoles) and environments (apps, web) and is not exclusive to connected TV (CTV). 


Connected TV (CTV)

CTV is a subset of OTT. A large TV screen that is connected to the internet, either directly (like a Smart TV) or through a gaming console or streaming device (e.g. Apple TV, Roku etc.). Video content is delivered to a TV screen, via the internet. A media buy of CTV inventory can generally be assumed to be running in a large screen format.

Advanced TV

An umbrella term referring to any TV content that has evolved beyond traditional, linear TV delivery methods. Advanced TV describes new digital advertising capabilities and impression-based delivery applied to premium video content. Advanced TV generally encompasses OTT/CTV, VOD and addressable / data-driven linear TV.


Addressable TV (ATV) 

ATV is the ability to serve different ads to different target groups and audience segments watching the same linear TV content. This helps deliver more relevant ad content to each viewer. Addressable advertising combines the reach and power of linear TV with the possibility to be precise with data-driven targeting such as demographic profile, viewing behaviour, interests, and location. Three types of technologies are used for the delivery of ATV: HbbTV, IPTV, and OTT.


Internet Protocol television (IPTV)

A subset of CTV, Internet Protocol television is the delivery of TV content over Internet Protocol (IP) networks (i.e. a closed, proprietary and optimised network). In contrast to delivery through traditional terrestrial, satellite and cable TV formats, IPTV offers the ability to stream live or on-demand content via a connected device. 


Hybrid broadcast broadband TV (HbbTV)

HbbTV is an international consortium and standard aimed at combining the broadcast and broadband delivery of interactive entertainment services to consumers. In practical terms, this means that you can get both standard broadcast FTA (free-to-air) TV and IPTV (internet delivered) TV services all in one place. This standard is integrated into all European TV sets.
Interactive services include for instance call-to-action or gaming functionalities, or enable addressability through overlay or interactive banners on the TV set. 


Linear TV

The traditional system in which a viewer watches a scheduled TV programme when it's broadcast and on its original channel.


On Demand

Video-on-demand (VOD)

A service that allows viewers to watch video content wherever and whenever they choose, rather than at the scheduled broadcast time.


Subscription VOD (SVOD)

A video content service for which the user pays a subscription in order to access content e.g. Netflix, Amazon Prime, Britbox etc.


Broadcaster VOD (BVOD) 

A video content service delivered by a broadcaster, which is typically funded by advertising, and is therefore free to the user.


Ad-supported VOD (AVOD)

A video content service that is funded by advertising. This includes video services that are free to the user and hybrid solutions, which offer a subscription fee as well as showing ads. Broadcaster VOD services (e.g. ITV Hub) that are funded by advertising are included in this, but also YouTube, PlutoTV,  etc. By using ad revenue, publishers can give viewers access to content for free or at a reduced rate.


Transactional VOD (TVOD)

A video content service where customers pay for each piece of video on demand content. For example, a customer would pay a fee for each movie or TV show that they watch. TVOD services, like Apple’s iTunes, enable one-off purchases and often time-limited access.


Live streaming

Content that can be streamed in real-time over the internet.


Free ad-supported streaming TV (FAST)

Sometimes called FAST channels, these allow viewers to stream live TV without paying for a subscription. 


Buying & Selling

Programmatic TV 

An automated approach to buying and delivering audience-based TV advertising through a software platform. 



CTV video ad spending committed in advance.


Ad pods

Ad pods are groups of ads played back-to-back, like a commercial break on TV.


Ad slots

An ad slot is an individual ad that plays within an ad pod. There can be multiple ad slots in each ad pod.


Ad podding / ad pod bidding

Ad pod bidding is a way of auctioning inventory that allows publishers to expose an entire ad pod in a bid request. As a result, marketers get more transparency, and also reduce QPS. They can bid on one or multiple ad slots within each pod. For publishers, this helps maximise revenue and fill rate. Publishers can accept different ad slot sizes to maximise the full ad pod. 



Dynamic ad insertion (DAI)

Campaign optimisation technology that allows advertisers to dynamically change ads within VOD content, i.e. swap the ad creative shown, making it possible to target specific viewers rather than serving the same ad to each viewer. Can sometimes be referred to as SSAI, or server-side ad insertion.


Automatic content recognition (ACR)

The use of technology (watermarking of fingerprinting) to identify a piece of content (audio or video for instance). Watermarking adds an imperceptible and unalterable piece of code to uniquely identify a piece of content. Fingerprinting uses a reference database to match and identify a piece of audio or video content. ACR allows the integration of contextual ads.


Server-side ad insertion (SSAI)

Stitching the ads within the content prior to delivery in one single stream. This eliminates buffering and, as with DAI, allows for dynamic changes.


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