New to Optimizely, or just getting started with A/B testing? Or maybe you were just wondering what a certain term meant. Either way, our Glossary has got you covered.



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Term Definition
A/A Testing A method of comparing the same webpage or mobile app experience against itself to test the accuracy of the testing tool.
A/B Test (or Split Test) The common name for a test that puts one (or more) variations of a page (or pages) against one another and measures how the two variations perform against one another for specific defined metrics.
A/B/n Testing A method of comparing multiple versions of webpage or mobile app against each other to determine which performs best.
Account This is the highest level of the hierarchy in your Optimizely plan. Accounts contain projects, which contain experiments, which contain variations.
Administrator The Optimizely user role with access to all features, including billing.
Audience A group of visitors who share a characteristic, such as the way they came to your page or the browser they use. You target experiments based on audiences.
Average Order Value (AOV) The average dollar amount spent each time a customer places an order on a website or mobile app. A common metric for e-commerce sites.
Body Content This is the main column of content on the page. This is not to be mistaken with the HTML term "body" which is ALL the content that is on the page.
Breadcrumb The increasingly specific category links at the top of a webpage indicating the categorization the user has come from. For example, "Home > Clothing > Mens > Jeans".
Bucket When visitors see a given variation, we say they are "bucketed" into that variation. Similarly, a visitor may be "bucketed" into an experiment, meaning that they are eligible to see the variation.
Click Goal A goal that measures whether a visitor clicked a certain element on the page.
Code Editor The section of the Optimizely Editor where you can see and directly modify the variation code (created in jQuery).
Collaborator An Optimizely user who is granted access to a project by either the Administrator or Project Owner.
Conversion A particular action or event that the user either did or did not do. For example, make a purchase, complete a form, reach a page, click a button etc. All of those are conversion metrics.
Conversion Rate The number of conversions on a webpage or app divided by the total number of visitors.
Conversion Rate Optimization (CRO) The process of increasing the percentage of conversions from a website or mobile app.
Call to Action (CTA) The primary button or link on a page the company would like the user to click.
Content Management System (CMS) The platform that allows for editing and publishing of data to a website without simply coding an HTML page. CMS platforms allow users to centralize data editing, publishing and modification on a single back-end interface.
Direct Entry The user enters the site's domain by typing in the exact address. For example, in the URL bar a user enters "" and gets to the site.
Dimension An attribute of your visitors added through Optimizely's API. Unlike Audiences, which have binary (yes/no) values, dimensions can have multiple values.
Editor The section of Optimizely where you edit your variations within an experiment. It is divided into the Visual Editor and Code Editor. May also refer to the user role "Editor," which can create variations but not start/pause experiments.
Engagement Metric Usually an average or counting metric. For example, Average Pageviews, Time on Site, etc. Unlike a conversion metric, which tabulates if a user did/did not do something, an engagement metric asks to what extent some action was done.
Exact Match A URL match type that matches the exact string of text entered.
Experiment (or Test, or Campaign) Experiment is Optimizely's term for an A/B, Multivariate, or Multi-page test. Others may call it a test, or a campaign.
Full Factorial MVT When every single possible combination of the multivariate test is actually run as it's own unique variation. This is distinctly different from the Taguchi Method which runs a limited number of variations based on the ones that are expected to be the most different from each other. The benefit of Full Factorial is there is no guesswork but the downside is that by running so many variations you need a lot of traffic to run MVT tests.
Funnel (or Sales Funnel) The path taken by a potential customer through a website or app as they move towards becoming a customer.
Goal (or Conversion Goal) The success metric by which experiments are evaluated.
Headline Testing The process of developing multiple title variations for an article or piece of online media to determine which one performs the best.

A report showing where visitors click on a page, typically displayed as an overlay where more intense colors indicate higher visitor clicks.

Hero The large image at the top of the page. Sometimes this is called a "Rotating Hero" when it is a slideshow of images that rotates through many images.
Home Page The section of Optimizely where you can manage projects and experiments.
Implementation (or Snippet Implementation) The act of adding the Optimizely Snippet to your page.
Improvement (or Lift) The relative difference (percentage) in performance of one variation vs. another. For example, if one campaign converts at 5% and another converts at 10% that represents 100% improvement. If the alternate converted at 20% that would represent 400% improvement. Improvement is calculated as follows: (Winning Conversion Rate % - Old Conversion Rate %) - Old Conversion Rate % = % Improvement
IP Address An Internet Protocol address, this is the numerical label assigned to any device on a network. When using IP Targeting or IP Filtering, this is based on the IP address of the visitor.
JavaScript (or JS) A computer programming language. The Optimizely Snippet is written in JavaScript. You may also include custom JavaScript in an experiment, or use it to target experiments.
jQuery A JavaScript library that is included in the Optimizely Snippet, and also used to create variation code. You may exclude Optimizely's default jQuery and use your own, or use a trimmed version, if you would like.
Landing Page Optimization The process of improving elements on a landing page to increase conversions.
  The process of generating consumer interest for a product or service with the goal of turning that interest into a sale.
  A grouping of technologies that marketers leverage to conduct and improve their marketing activities.
Multivariate Test (MVT) An experiment that has multiple variations of specific elements. The experiment is defined by selecting the elements and their variations. The testing platform will then automatically generate the possible testing combinations of these. For example, a 3x2 MVT test is changing 3 elements with 2 variations per element. If a full factorial test is running, this will result in 3^2 (i.e. 9) variations. 
Multi-page Test (or Multi-page funnel test) An experiment that includes different changes across multiple pages, to measure the difference in visitor behavior across a funnel (such as product > cart > checkout), or across a whole site. When a visitor sees a variation on one page, that visitor will continue to see the variation across all other pages in the experiment.
Online Marketing The strategy for leveraging web-based channels to spread a message about a company’s brand, products, or services to its potential customers.
Options Menu The menu in Optimizely where you can configure most experiment-wide settings, such as URL Targeting and Traffic Allocation.
Organic Search A user performs a web engine search (Google, Bing, Yahoo etc.) and clicks on a non-paid link. 
Original (or Baseline) This is the baseline experience that is used to compare against the variation.
Pageview Goal A goal that measures whether a visitor views a specified page.
Pause To stop running an experiment.
Plan A subscription package within Optimizely.
Primary Conversion The most ideal action that you want visitors to take. This would usually be a purchase event or "Add to Cart" action, or a "Sign Up Now" form, depending on your business.
Project A subsection of an account. Each project has its own snippet, set of experiments, and set of collaborators.
Project Owner An Optimizely user role similar to Administrator, but limited to a project, and does not have access to billing.
Query Parameter Letters and/or numbers included in the query string portion of a URL that pass data to web applications. They look like: ?item=true
Query String A string of query parameters. They are separated with an ampersand, as follows: ?item1=true&item2=false
Rail A smaller width column on the left or right side of the page that is not part of the "Main Body" content. 
Regular Expressions (or RegEx) A type of syntax used to match text strings. It is a match type within Optimizely's targeting.
Results Page The section of Optimizely where you can see the results of your experiments and determine the winning variation.
Revenue Per Visitor (RPV) The average dollar amount spent per each customer on a website or mobile app. A common metric for e-commerce sites.
Search Engine Marketing (SEM) Paid search campaigns. A company pays a search engine (i.e. Google) to get their paid link to show up when certain search conditions are met. 
Search Engine Optimization (SEO) Techniques done to a website (making sure keywords are shown, shown high on the page etc. etc.) to get the page to display higher on natural search results without paying the search engine is known as SEO.
Secondary Conversion This is the "next-best" action you would want visitors to take, compared to the Primary Conversion. Generally, this will occur "up the funnel" and be a leading indicator of success. These may include viewing product pages or requesting additional information, depending on your business.
Segmentation The process of analyzing only a subset of traffic in an experiment's results, to see if that group's behavior is different from the average. On Optimizely's results page, you can segment results by audience or dimension, depending on your plan.
Shopping Cart Abandonment When a potential customer starts a check out process for an online order but drops out of the process before completing the purchase.
Simple Match A URL match type that will match a given URL, without taking into account https://, query parameters, and other common modifications to a URL.
Snippet (or Optimizely Snippet) A line of JavaScript code that enables you to use Optimizely when placed on your page. There is one snippet per project in Optimizely.
Statistical Significance The likelihood that the difference in conversion rates between a given variation and the baseline is not due to random chance.
  Optimizely's proprietary way of calculating experiment results that allows you to interpret results without waiting for a fixed test duration and reduces the chance of false positives.
Substring Match A URL match type that will match a string within a URL. For instance, 'ample' is a substring match for ''
Taguchi Method A way to reduce the number of variations in an MVT so not every single variation has to be tested. The results of a Taguchi Method MVT is that the "best predicted" variation is displayed even if that variation was not an actual variation that was tested. Optimizely uses Full Factorial MVT testing.
Targeting The process of determining whether visitors will be included in an experiment. In Optimizely, URL Targeting determines whether an experiment will run on a certain URL, and Audiences determine whether an experiment will run for visitors who have certain characteristics.
Unique Visitor A distinct individual who visits a page during a given period, regardless of how often they visit (contrast with "visits").
URL (or Web Address) Stands for Uniform Resource Locator. This is the web address of a site, as you would see it in the address bar of your browser.
URL Targeting A way of specifying the pages on which your experiment will run.
User Flow The path taken by a prototypical user on a website or app to complete a task.
User Role A level of access within Optimizely. Optimizely's user roles include administrator, project owner, editor, and viewer.
Value Proposition (Value Prop) The essence of the value that your product or service provides to the customer.
Variation An alternate experience that is tested against the original in an A/B test. 
Variation Menu The menu in Optimizely where you can configure settings for individual variations, and preview them.
Viewer An Optimizely user role that can only view experiments.
Visitor An individual person who goes to your site.
Visits The number of times anyone has gone to your site within a given period. A unique visitor may have several visits.
Visual Editor (or WYSIWYG Editor) The part of the Optimizely Editor where you can edit your variations visually. (WSYIWYG stands for "What You See Is What You Get")
Winner The best performing variation of a test based on the most important metrics. A given campaign may have multiple winners if there is no single clear metric that defines which variation will be implemented. 


Looking for a certain term that doesn't appear here? Let us know by clicking the blue "Feedback?" tab on the right side of this page. See also our Optimization Glossary.