Glossary of Terminology

Note: The following definitions describe terminology as it specifically relates to interactive advertising designed for Internet websites.


Term Definition
Animation A programmatically generated display of sequential images, creating the illusion that objects in the image are moving. Not digital video, as it relates to this document (see the definition for “Video”).
Audio The audible file that may accompany ads. Advertising audio should not play without user-initiation in general. See detailed IAB New Ad Portfolio guidance for when it can be played without user initiation.
Banner Also known as “display ads”, banner advertisements are a form of graphical ads embedded into a webpage, typically including a combination of static/animated images, text and/or video designed to convey a marketing message and/or cause the user to take an action. Banner dimensions are typically defined by width and height, represented in pixels.
Between-the-Page Also known as “interstitial” ads, between-the-page ad units display as a user navigates from one webpage to the next webpage. The ad appears after the user leaves the initial page, but before the target page displays on the user’s screen. The ad is self-contained within its own browser window and may not appear as an overlay on the target page content.
Billboard An IAB Universal Brand Package ad unit template designed with options for rich interactivity to display prominently inline with Publishers’ webpage content. A distinct feature of the Billboard is a close button that a user may click to collapse the ad completely if the user doesn’t want to see the ad.
Bitrate The rate of bits processed per unit of time, commonly measured in bits per second (bps), kilobits per second (Kbps), or megabits per second (Mbps). The bitrate is one of the biggest factors in audio or video quality.
Button 2 A small rectangular standard ad unit with the size 120×60 pixels.
Byte A unit of digital information in computing and telecommunications that most commonly consists of eight bits. Historically, a byte was the number of bits used to encode a single character of text in a computer and for this reason it is the basic addressable element in many computer architectures.
Caching The practice of temporarily storing files on local servers for quick retrieval the next time the file is needed. Cached files supply an old copy that may not be up to date with the file stored at the original source, but are often necessary for improving page load performance.
Campaign The advertising period in which an ad delivery strategy is executed.
CDN An acronym for Content Distribution Network, a CDN is a system of geographically dispersed servers used to provide web content to a browser or other client. Files are strategically pulled from a server on the network based on the location of the user, the requesting server, and the delivery server of the CDN to provide the best delivery performance.
CLEAR Ad Notice CLEAR is an acronym for “Control Links for Education and Advertising Responsibly,” a set of technical guidelines developed by the Interactive Advertising Bureau (IAB) and the Network Advertising Initiative (NAI) to empower members of the online advertising community to communicate their presence and behavioral advertising targeting practices (if any) to consumers in a simple and direct manner. Derived from:
Click An interaction between a website visitor and the browser in which the website visitor uses a device, such as a mouse, to move the cursor (or pointer) to an active area of the screen and then deliberately interacts with that area by clicking a button on their device, triggering an event. In the case of touch-screen devices, the user “clicks” by touching the active area with their finger or a stylus.
Close X A creative control that enables a user to close an ad (remove it from view) or to reduce an expanded panel back to its original size.
Collapse An event where the expanded panel of an expandable ad reduces to its original size, or disappears completely.
Compression The practice of packaging a digital file so that it uses less storage space.
Controls Active elements of an ad that enable a user to control the advertising experience. Examples of common controls include the “Close X” button in an expandable ad or the Play/Pause/Mute buttons in a video player.
CPU CPU is an acronym for Central Processing Unit, the key component of a computer system, which contains the circuitry necessary to interpret and execute program instructions.
CPU Usage % A guideline for the amount of central processing power used to display advertising content compared to what’s available on an individual’s computer. CPU usage percentage can be measured directly, during the execution of an online ad. In addition to file size, the complexity of drawings, gradients, slow moving animations and detailed moving elements can affect the number of calculations the CPU must make for each frame.
CPU Spike A brief increase in central processing power, sustained for no more than a few seconds, experienced while “heavy” content is loaded/executed.
Creative An advertising unit created by an ad designer, in accordance with publisher specifications and guidelines, for the purpose of communicating a marketing message to that publisher’s audience. One creative may consist of multiple files in various formats, such as standard images, animation, video, execution files (.html, .js, etc.) and other files that work together for an interactive experience.
Creative Dimensions Measured in pixels, the width and height of an ad unit (WxH). The width is always the first dimension listed, followed by the height dimension (i.e. an ad that is 300×250 is 300 pixels wide by 250 pixels high).
Cursor The graphical representation of a “pointer” on a user screen, controlled by the user’s interaction with controlling devices such as a mouse, mouse pad, stylus or other input hardware.
Expandable Ads Rich media ads that can be enlarged to dimensions beyond the initial dimensions of the placement they fill on the webpage. The user initiates expanding events, sometimes after the ad initially expands briefly on its own to catch the user’s attention.
Expanded Dimensions The secondary dimensions of an expanding ad unit (after the ad is expanded). Initial dimensions are fit to the dimensions of the placement. Then, either by auto-play or by user interaction, the ad unit expands to its secondary dimension.
File requests In the context of displaying digital content, the browser loads code that contains instructions about where to retrieve files such as text, images, videos, and any other components that contribute to the display experience. Each time the browser must retrieve content from another server, a file request is made. Too many file request may reduce page load performance.
Filmstrip An IAB Universal Brand Package ad unit template that is 350×3000 pixels, divided into five 350×600 pixel segments that scroll by user interaction though a 350×600 pixel placement “window.”
Flash™ Software and tools developed by Adobe used to build, generate, and play animated files. Also used to define the creative files generated by the program. In order for Flash files to execute in a browser, the Flash player plug-in must be installed. However, Flash development tools can also generate files in HTML5 format so that no plug-in is required for execution.
FPS FPS is an acronym for Frames Per Second, the metric used to indicate the frame rate of animated or video creative content.
Frame Rate The rate at which video frames or animated images display as the video or animated file executes, measured as the number of frames per second (fps).
GPU GPU is an acronym for Graphics Processing Unit. In modern computers, the GPU handles graphical processing, decreasing the processing burden handled by the CPU.
Gzip Automatic compression of creative assets for an ad when delivering from an ad server to a web page or application. The key difference between .zip files and gzip is that zip is used for storing files, and gzip is used for compressing files that are in transmission from one server to another.
H.264 A video coding format that uses a block-oriented, motion-compensation-based video compression standard. H.264/MPEG-4 AVC is one of the most common formats used for recording, compressing, and distributing video content.

For more information see:

HLS An acronym for HTTP Live Streaming is an HTTP-based media streaming communications protocol implemented by Apple Inc. It works by breaking the overall stream into a sequence of small HTTP-based file downloads, each download loading one short chunk of an overall potentially unbounded transport stream. As the stream is played, the client may select from a number of different alternate streams containing the same material encoded at a variety of data rates, allowing the streaming session to adapt to the available data rate. At the start of the streaming session, it downloads an extended M3U playlist containing the metadata for the various sub-streams [that] are available. See for more information.
Host-initiated Any activity that is auto-initiated.
Host-initiated sub-load The additional file limit allowed that is auto-initiated after the load event is fired by the window object of the publisher page (intial web page content has been loaded) on the host computer or device. In absence of access to publisher page window object, the window object of the ad iframe can be used.
Hot Spot A “hot spot” is an area of an ad unit, which when rolled-over/rolled-on by the user’s cursor, such rollover triggers an event (i.e. expand ad). The hotspot should never be larger than 1/4th the size of the original (collapsed) ad unit. The trigger event should not occur unless the user’s cursor rests in the hotspot zone for at least 1-second. Hotspots should never initiate audio (audio should only be initiated by a click). When hotspots are used, the trigger event should stop immediately upon the user’s cursor leaving the hotspot zone (i.e. ad collapses), and the ad unit should return to its original state.
HTML5 An acronym for Hypertext Markup Language, version 5. HTML5 extends earlier versions to include tags for processing video, audio, canvas, an other embedded audio and video items without requiring proprietary plug-ins and APIs. HTML5 has been used as an alternative to developing and executing interactions similar to those using Adobe Flash but with very different technology.
IBA Interest-based advertising — which is also sometimes called “online behavioral advertising” — uses information gathered about a site user’s visits over time and across different websites or applications in order to help predict preferences and show ads that are more likely to be of interest to you. For example, a sporting goods manufacturer might work with an advertising network that collects and uses interest-based advertising information to deliver ads to the browsers of users that have recently visited sports-related sites, or an airline might direct ads to users that recently visited mobile travel apps. Definition from site:
In-Banner Video A video delivered as part of (inside of) the display ad creative for a given placement rather than initiating the use of a video player.
Initial Dimension The original width and height (in pixels) of an expanding ad. Expanding ads are designed to expand to dimensions larger than the initial dimensions.
Initial File Load Includes all assets and files necessary (.html, .js, .css, .woff, images, ets.) for completing first visual display of the Ad. The initial file load size of an ad is limited in order to preserve the page load performance and thus the user’s web browsing experience. For non-rich media ads, the initial file load size limit is all that’s allowed for the ad.
Interstitial See ‘Between-the-Page’
JavaScript libraries A collection of pre-written code used to simplify development of web-based applications.
Kilobyte (KB) A multiple of the unit ‘byte’ for digital information, used to quantify computer memory or storage capacity equal to a 1,000 bytes (or technically, 2^10 = 1,024 bytes). For the purposes of this document, this measure relates to creative file size. (See definition for Byte)
Labeling Requirements The minimal requirements for distinguishing an online advertisement from regular webpage content.
Megabyte (MB) A multiple of the unit ‘byte’ for digital information, used to quantify computer memory or storage capacity equal to 1,000 kilobytes (or technically, 2^20 = 1,048,576 bytes). For the purposes of this document, this measure relates to creative file size. (See definition for Byte)
Minification The practice of removing unnecessary characters from code to reduce its size, removing unnecessary spacing, and optimizing the CSS code; thus improving load times.
moov atom A video data object in a media file used to execute the video. The moov (or movie) atom should be placed at the beginning of a video file to ensure proper execution.
Mouse-off The act of a user moving the cursor away (off) from the hot spot of an ad. Mouse-off by a user may trigger an event, such as collapsing an expanding panel or stopping any animation in progress.
Mouse-over The act of a user moving the cursor and resting it on the hot spot of an ad for at least one second. Mouse-over may trigger an event such as expanding the ad or initiating an animated sequence within the ad. Mouse-over may NOT initiate audio play.
MP4 A digital multimedia format used to store video and audio, but may also include features such as subtitles, chapter details, and other data related to the video or audio file. The filename extension for MPEG-4 files is .mp4.
MPEG A set of standards for audio and video compression and transmission established by the Moving Picture Experts Group.
MPEG-DASH An acronym for MPEG Dynamic Adaptive Streaming over HTTP. This adaptive streaming technique allows for a streaming experience using progressive download of several small chunks of video at different bitrates. An HTTP-connected video player (the client) detects the bandwidth at each chunk of time (about 3-5 seconds) and determines which quality level to download and play for the small duration allotted.
MRAID An acronym for Mobile Rich Media Ad Interface Definition. MRAID is a protocol that enables communication between an ad and a mobile application in order to execute interactions such as geolocation, ad resizing, and accelerometer functions among others.
OBA Self-Regulation See “IBA”
Overlay An ad unit that displays over the webpage content briefly when initiated.
Pause A video, animation or audio control that enables users to stop the video, animation, or audio from playing until the user is ready to resume play.
Pixel (as a unit of measure) The smallest unit of measure for graphical elements in digital imagery, used as the standard unit of measure for ad creative (i.e. 300×250 pixels). Pixels may also represent x/y coordinates relevant to a given space, such as the browser window, an application workspace or the user’s computer screen. (See also “Tracking Pixel”)
Pixel Density The number of pixels displayed on the screen within an inch (pixels per inch or PPI) or within a centimeter (pixels per centimeter or PPCM). Screen pixel density varies by device with older monitors displaying 67 – 130 PPI. Mobile devices often exceed that at 300+ PPI. Pixel density of 163 PPI is referred to as pixel density of 1 in this document.
Play A video, animation or audio control that enables a user to initiate (or avoid initiating) the video, animation or audio of an ad.
Polite file load Withholding a portion of the total ad creative file size (besides any initial file load size) from loading on a page until publisher content has loaded. With the release of the Display Creative Guidelines in 2015, polite file load has been replaced “Host-initiated subload.” See Host-Initiated Subload for definition.
Pop-up Ad Any advertising experience where visiting a website in an initial browser window initiates a secondary browser window to deliver an ad impression directly above the initial browser window.
Portrait An IAB Rising Star ad unit template that uses up to three interactive modules chosen (by the ad designer) from a variety of modular application options in a 350×1050 pixel space.
Progress Bar A video or animation control that shows users the progression of the video or animation in relation to its total duration.
Progressive Load Video A distribution method for serving video files in which the video file downloads progressively into the cache of a user’s computer, much the same way images and other content elements are downloaded. HTML5 files use progressive download for video files, but streaming methods can be simulated using adaptive bit streaming technologies such as HLS and MPEG-DASH.
Pushdown An IAB Rising Star ad unit template designed for rich interaction in a space similar to, but larger than, an expanding leaderboard, with initial dimensions of 970×90 pixels and expanded dimensions of 970×415 pixels. When the ad is expanded, it “pushes” page content down rather than displaying over the top of page content as most expandable ads do.
Resolution The quality of an image or video file often determined by the number of pixels displayed on the screen and usually annoted as a pixel width and height dimension. However, resolution can be measured in a number of ways and takes into account pixel aspect ratio, pixel density, and other factors that determine the viewing quality of the file.
Retraction An event programmed into an expandable ad the causes the ad to be reduced to its original dimensions (i.e. the expanded portion of the ad retracts).
Rising Stars Display Ad Units IAB invited companies and individuals to submit ad templates designed to drive brand equity. Six templates were chosen to be validated by the market. Universal Brand Package Display Ad Units are designed to be the only ad on a page. Their file load limits are larger than for other ads, so not only would a Universal Brand Package Ad Unit overshadow any other ads on the page but they would also compromise the performance of the page should other rich media ads be allowed to load simultaneously. Please refer to the IAB New Ad Portfolio. The Rising Stars are in transition. They are under evaluation and will be delisted soon. Publishers should transition to the aspect ratio ad units with flexible ad sizing listed in the new ad portfolio.
Rollover  The willful pause of the user’s cursor on the target portion of the creative (the “hot spot”), such pause lasting at least one second in duration, before an action may be initiated by the ad (i.e. trigger an expand event, etc.). This one-second pause/delay requirement prevents unwanted, user-initiated actions and false reporting of user engagement. Rollover may NOT initiate audio.
Shared Libraries In digital advertising, shared libraries are collections of pre-written code and resources that are used for implementing features and functions for an HTML5 ad. Instances of such resources that are downloaded to the browser from a specific server, like a CDN, are cached on the browser. Once cached, shared libraries can be shared with other ads that reference the library and the host server.
Sidekick An IAB Rising Star ad unit template initially displayed as one of three standard ad unit dimensions, but upon user initiation, “pushes” publisher content to the left to display a canvas of up to 970×550 pixels full of rich interaction.
Skyscraper A standard ad unit with dimensions of 160×600 pixels.
Slider An IAB Rising Star Ad Unit template designed with an overlay “slider” (90 pixels high) that rests at the bottom of a publisher’s page and when prompted by user interaction, slides page content to the left for a canvas of 970×550 pixels full of rich interaction possibilities for user engagement.
Standard Ad Units A set of ad specifications for standard image or animated in-page ad units that establish a framework for advertising inventory and webpage design. The current recommended ad units are the IAB New Ad Portfolio.
Streaming Video A distribution method for serving video files such that the video is played over a persistent connection between the browser and the ad server. Versions of the file at different levels of compression (quality) can be served based on detection of the user’s Internet bandwidth. HTML5 files cannot be streamed and rely on adaptive bitrate streaming technologies such as HLS and MPEG-DASH.
Submission Lead Time The number of business days (non-weekend/non-holiday days) prior to a campaign going live in which a publisher needs to validate advertiser submitted creative(s) for a campaign.
Supporting files In the context of HTML file loads, supporting files are files that the browser needs to reference in order to execute display of file contents and any interactions. Examples of supporting files include JavaScript libraries, font libraries, CSS files, and others.
SWF Acronym for Shockwave Flash™. “.swf” is the file naming extension used for animated files complied using Adobe Flash™ software. HTML cannot execute .swf files without the browser-installed Flash player plug-in. For this reason, many content and ad providers are moving to the HTML5 format for more efficient execution of interactive media files.
Tracking Pixel A 1×1 pixel-sized transparent image that provides information about an ad’s placement. In many cases, a tracking pixel is used to notify an ad tracking system that either an ad has been served (or not served, in some cases) or that a specific webpage has been accessed. Also known as: beacon, web beacon, action tag, redirect, etc.
Universal Ad Package (UAP) A set of four ad units (728×90, 300×250, 160×600 and 180×150 pixels) offered by UAP-compliant publishers as a ‘package’ where ads in these four formats are used collectively across the publisher’s site, enabling advertisers to reach more of the publisher’s audience. Those UAP ad units are no longer recommended nor supported by IAB. They are now replaced by the IAB New Ad Portfolio.
Universal Brand Package (UBP) Display Ad Units See “Rising Stars”
User  An anonymous person who uses a web browser to access Internet web content.
User Initiation  The willful act of a user to engage with an ad. Detailed guidance is provided in the IAB New Ad Portfolio document. Users may interact by a discrete device action like clicking on the ad, and/or tapping over an ad (or a portion of an ad). Rollover is not a valid user initiation action.
Video (aka “Digital Video”) In online advertising, the digital recording of a physical event or animated files that have been transcribed into a digital video format.
Volume A control that enables users to adjust the audio output of ad creative. Volume controls should always allow adjustment down to zero (0) output.
VP8 A video compression format owned by Google and created by ON2 Technologies. Latest version is VP9.
WebM WebM is a video file format. It is primarily intended to offer a royalty-free alternative to use in the HTML5 video tag. The development of the format is sponsored by Google, and the corresponding software is distributed under a BSD license.
Z-index Enumerated layers of elements and content on a publisher’s webpage. Consideration of the z-element in page content design such as navigation, imagery, and ads is important for providing a seamless experience when page content overlaps (i.e. an expanding ad with a z-index that is lower [on the z-index scale] than navigational elements may give the appearance that page navigational elements are showing through the expanded portions of the ad).