Call To Action (CTA) is typically a button or a link that is placed strategically on the page so that the user will notice it and interact with it. Typically CTAs are used to entice users to signup for service, subscribe to a newsletter, try a product, or buy something.
Often user flow (or task flow) is designed with multiple CTAs in place each leading to deeper and deeper commitment from the user. For example, a hero unit on the website describes a product or a service that company is selling, but CTA says “Learn more”. Call to Action to buy the product might not be shown until further down the detailed page that describes all the benefits of that particular product/service.
Sometimes designers use multiple calls to action on the same page. Typically, we differentiate between primary and secondary calls to action giving more prominence to primary CTAs.
Clever example of CTAs
Some products use CTAs in a particularly creative and clever way, luring the user into the registration funnel. For example, SquareSpace takes users through a series of steps of setting up a website before asking for registration:
Note that the final CTA in the funnel is not a payment form. SquareSpace automatically enrols the user into a 14-day free trial of the site builder. CTA to upgrade is subtle, and is designed to stay out of the user’s way as one tries the product, but also to give the user a sense that he might be missing out on features.