Call to Action
A Call to Action (CTA) is a marketing term to define a designed element that solicits and encourages an action from the user and which the end goal is to attempt a sale. You'll hear a lot of this term when you start working as a designer when designing websites, especially for marketing purposes. The goal of every designer is to maximize the click conversion on this button, which leads to a sale at the end. Here is some indication of good practice when designing your CTA.
Making it obvious
One piece of advice I'll give is not to be too creative when designing a CTA because it remains a button, and people are used to it. As users have become accustomed to the online experience, they know that CTAs come in the forms of buttons. They see a button; they know what to do. Simple. Make it big, obvious, and stand out from everything around it, and it's in the bag.
Here's an example of a bad CTA:
Image from Capgemini.com website 2017. All rights reserved to Capgemini
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