A visit simply depicts the number of times an individual user had a unique session on a particular website. Whereas, click signifies the number of times a visitor clicked on advertisement which has been placed on your website.
let me simplify this for you:
Clicks: It indicates the number of times a user clicks on your ad.
Visits: It indicates the number of unique sessions associated with each of the visitors.
Clicks: An ad can be clicked several times by the same visitor which results in several clicks to be recorded.
Visits: A visit made by a unique visitor is recorded only once in a single session. (Session is of 30 minutes.)
Clicks: If any user visits a website by clicking on an ad and also visit it again by clicking any bookmark url.
Visits: A visit made from advertisements clicks in such case sessions could impact in several from a single click
Clicks: Google AdWords tracks clicks.
Visits: Google Analytics tracks visits.
Clicks: AdWords filters out invalid clicks generated within.
Visits: Analytics displays all data without any filtering.
You must read this: Mistakes you are making with google analytics
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