A goal is the primary metric you want to impact with an optimization. The goal could be account sign ups, demo requests, or any other measurable conversion.
A single goal can have many goal events. Triggering any of the goal events is counted as a successful conversion with respect to that goal.
Example: Your site has multiple "Sign up" buttons. Clicking any of the buttons is a goal event for the common signup goal.
An audience is a group of visitors you want to target with a custom experience.
The holdout is the percentage of visitors that will not receive any of the custom experiences. Instead, they will see the site in its original state.
An override is a modification to the web site, made with the Visual Editor, such as swapping an element's style or content, or redirecting to another page.
The base url is the full top-level path of the site to be optimized (e.g.
https://www.company.com). All overrides are made to relative paths of the base url.
An experiment splits traffic between multiple variants and reports the conversion rates for each. The experiment runs until the user decides to end it or restart it.