CAPTCHA is a technology that distinguishes humans from machine input. This makes it a lot more difficult to create spam accounts.
This function is disabled by default. To enable it, Site Managers can go to the dashboard and enable this function on the 'Spam Protection (CAPTCHA)' page.
When enabled, new users need to click the checkbox before being able to create an account.
This feature makes use of Google service. Please take this into account as you need to update your data policy accordingly if you choose to use the service.