The captive portal is also known as captive portal login.
The principle of the captive portal is to allow a person to connect to a Wi-Fi network, under the condition of providing identifiers (e-mail, name, first name…).
During the identification, the user is redirected to a web page with normally a form to fill. This automatic redirection to the portal is called Catch and Release.
Captive portals also have an opt-in/check box to indicate acceptance of the terms and conditions of use. This is essential, especially in the context of the General Data Protection Regulation (GDPR).