CTA stands for call to action, which is basically a message that nudges your app user, website reader, podcast listener, or customer to undertake a specific action.
The call to action can take the form of a button or a text link that tells a reader to click or do something. In digital marketing, this typically asks them to download a white paper, view a video, schedule a demo, or visit a web page that brings the visitor further into your site.
First and foremost, the CTA leads a visitor to convert. This may mean accomplishing an action such as contacting you, purchasing a product, requesting an estimate, or downloading a resource.
Secondly, the CTA helps increase your click-through rate, which is basically the number of pages an average visitor will view when they land on your website. The better your click-through rate, the better your ranking in search engine results pages (SERPs). In short, it boosts your SEO.
There are many resources online on constructing better CTAs, but they all generally direct you to do three main things.
You should run A/B tests to find the combinations that appeal to your target audience and generate the KPIs you need.