Glossary
What is SSL?
The older name commonly used for TLS. Modern HTTPS connections use TLS.
Hosting panels and everyday descriptions still commonly say SSL certificate, although modern secure web connections use TLS. When installing a certificate, check the required hostnames and the server certificate chain. When reading an SSL check, consider which certificate was presented and for which target.
Example
A certificate installed through an Upload SSL certificate option in a panel can be used by TLS in a modern HTTPS connection.
Common issue
The common use of the name SSL does not make old SSL protocol versions current or safe. Fix hostname, date and chain problems rather than disabling browser verification.