An SSL/TLS certificate lets a browser establish an encrypted HTTPS connection with a website. Encryption helps protect information while it travels between the visitor and the server.
Configure HTTPS throughout the site
After installing a certificate, check that pages and resources load over HTTPS. Redirect the HTTP version, update internal links and test forms so that parts of the page are not left unencrypted.
Keep the certificate current
Certificates expire. Check who manages renewal and confirm that browsers open the site without certificate warnings.