What is a target audience? Target audiences allow tests to show an experiment or campaign to a specific group of visitors who visit a site site, based on specified conditions. For example, this allows optimisation experiments to target visitors who’ve seen a specific AdWords campaign or show an experiment to visitors on mobile devices only.
What is a variation(s)? A variation is the altered version(s) of a page which is different from the control in some way.
What is visitor segmentation? Visitor segmentation is the process of dividing your visitors to your website based on a specific criteria, such as demographics or user behaviour.