A conversion occurs when a visitor to a website performs a task that the website owner intended, for example, signing up for a service or downloading an eBook. Conversions are often the point when a visitor becomes a customer or takes a step closer to becoming a customer.
Conversion rate is the ratio of visitors that perform a certain conversion task. For example, if 100 users visit a landing page designed to get them to sign up for a free trial of a service, and 50 of them opt to do this (or convert) the conversion rate would be 50 out of 100, or 50%.
Improving conversion rate is a key task of all digital marketing teams. A/B testing is a common way to refine and optimise pages to discover new ways in which they can convert visitors into customers.