The consent checkbox is a checkbox that the user must check in order to be allowed to save. It is used for things like:
Unlike the normal Checkbox control, which is never mandatory, the Consent Checkbox is always mandatory.
For the best user experience you should configure a mandatory message on the field when using a consent checkbox, so that users get an error message like "You must consent to having your personal data stored." instead of the default "'I consent to having my personal data stored' is mandatory!"