From O to P

Off-site measurement

When a site forwards its log files to an off-site Web research service for analysis.


The ability to request video, audio, or information to be sent to the screen immediately by clicking something on the screen referring to that choice.

On-site measurement

When a server has an appropriate software program to measure and analyze traffic received on its own site.

OPA(Online Privacy Alliance)

A group of corporations and associations who have come together to introduce and promote business-wide actions that create an environment of trust and foster the protection of individuals’ privacy online. See for more information.

OPA(Online Publishers’ Association)

Trade association representing a segment of online publishers. See for more information.


Refers to an individual giving a company permission to use data collected from or about the individual for a particular reason, such as to market the company’s products and services. See permission marketing.

Opt-in e-mail

Lists of Internet users who have voluntarily signed up to receive commercial e-mail about topics of interest.


When a company states that it plans to market its products and services to an individual unless the individual asks to be removed from the company’s mailing list.

OTS(Opportunity to See)

Same as page display-when a page is successfully displayed on the user’s computer screen.

P3P(Platform for Privacy Preferences Project)

Browser feature that will analyze privacy policies and allow a user to control their privacy needs.

Packet sniffer

A program used to monitor and record activity and to detect problems with Web transactions on a network.


A document having a specific URL and comprised of a set of associated files. A page may contain text, images, and other online elements. It may be static or dynamically generated. It may be made up of multiple frames or screens, but should contain a designated primary object which, when loaded, is counted as the entire page.

Page display

When a page is successfully displayed on the user’s computer screen.

Page impression

A measurement of responses from a Web server to a page request from the user’s browser, which is filtered from robotic activity and error codes, and is recorded at a point as close as possible to the opportunity to see the page by the user.See for ad campaign measurement guidelines.

Page request

The opportunity for an HTML document to appear on a browser window as a direct result of a user’s interaction with a Web site.

Page view

When the page is actually seen by the user. Note: this is not measurable today; the best approximation today is provided by page displays.


A group of letters and/or numbers which allow a unique user access to a secured Web site and/or a secure area of a Web site.


An advertising pricing model in which advertisers pay agencies and/or media companies based on how many users clicked on an online ad or e-mail message.


An advertising pricing model in which advertisers pay based on how many users were served their ads. See CPM pricing model.


An advertising pricing model in which advertisers pay for each “sales lead” generated. For example, an advertiser might pay for every visitor that clicked on an ad or site and successfully completed a form. See CPL.


An advertising pricing model in which advertisers pay agencies and/or media companies based on how many sales transactions were generated as a direct result of the ad. See CPS.

PDF files(Portable Document Format)

A translation format developed by Adobe used primarily for distributing files across a network, or on a Web site. Files with a .pdf extension have been created in another application and then translated into .pdf files so they can be viewed by anyone, regardless of platform.

Performance pricing model

An advertising model in which advertisers pay based on a set of agreed upon performance criteria, such as a percentage of online revenues or delivery of new sales leads. See CPA, CPC, CPL, CPO, CPS, CPT.

Permission marketing

When an individual has given a company permission to market its products and services to the individual. See opt-in.

Persistent cookie

A cookie which remains on the user’s hard drive until the user erases it.

PII(Personally Identifiable Information)

Refers to information such as an individual’s name, mailing address, phone number or e-mail address.

PIN(Personal Identification Number)

A group of numbers which allow a unique user access to a secured Web site and/or a secure area of a Web site. See password.

PIT(Page Information Transfer)

The successful transfer of the text of a Web page to a browser.


Picture element(single illuminated dot)on a computer monitor. The metric used to indicate the size of Internet ads.


The type of computer or operating system on which a software application runs, e.g., PC, Macintosh, Unix or WebTV.

PLI(Privacy Leadership Initiative)

A partnership of CEOs from 15 corporations and 9 business associations using research to create a climate of trust that will accelerate acceptance of the Internet and the emerging Information Economy, both online and offline, as a safe and secure marketplace. See


A program application that can easily be installed and used as part of a Web browser. Once installed, plug-in applications are recognized by the browser and their function integrated into the main HTML file being presented.

Pop-under ad

Ad that appears in a separate window beneath an open window. Pop-under ads are concealed until the top window is closed, moved, resized or minimized.

Pop-up ad

Ad that appears in a separate window on top of content already on-screen. Similar to a daughter window, but without an associated banner.

Pop-up transitional

Initiates play in a separate ad window during the transition between content pages. Continues while content is simultaneously being rendered. Depending primarily on line-speed, play of a transitional ad may finish before or after content rendering is completed.


A Web site that often serves as a starting point for a Web user’s session. It typically provides services such as search, directory of Web sites, news, weather, e-mail, homepage space, stock quotes, sports news, entertainment, telephone directory information, area maps, and chat or message boards.


Storing advertising or content in a computer’s RAM or hard disk memory before it is displayed on the user’s screen, rather than at the time that it plays, to reduce delays in rendering. See cache, caching.

Privacy policy

A statement about what information is being collected; how the information being collected is being used; how an individual can access his/her own data collected; how the individual can opt-out; and what security measures are being taken by the parties collecting the data.

Privacy seal program

A program that certifies the Web site owner complies with the site’s proposed policy. Examples include TRUSTe and BBBOnline.


The practice of tracking information about consumers’ interests by monitoring their movements online. This can be done without using any personal information, but simply by analyzing the content, URL’s, and other information about a user’s browsing path/click-stream.

Process audit

Third party validation of internal control processes associated with measurement. See audit.


A uniform set of rules that enable two devices to connect and transmit data to one another. Protocols determine how data are transmitted between computing devices and over networks. They define issues such as error control and data compression methods. The protocol determines the following: type of error checking to be used, data compression method(if any), how the sending device will indicate that it has finished a message and how the receiving device will indicate that it has received the message. Internet protocols include TCP/IP(Transfer Control Protocol/Internet Protocol), HTTP(Hypertext Transfer Protocol), FTP(File Transfer Protocol), and SMTP(Simple Mail Transfer Protocol).

Proxy servers

Intermediaries between end users and Web sites such as ISPs, commercial online services, and corporate networks. Proxy servers hold the most commonly and recently used content from the Web for users in order to provide quicker access and to increase server security.

Push advertising

Pro-active, partial screen, dynamic advertisement which comes in various formats.

PVR(Personal Video Recorder)

Set-top box that stores up to 30 hours of TV programming and works with cable and satellite systems. Viewers can pause or rewind live TV shows, record a season’s worth of episodes, and skip past commercials.