SSL

• SSL, or Secure Sockets Layer, is an encryption-based Internet security protocol.

• It more commonly called TLS, is a protocol for encrypting Internet traffic and verifying server identity. 

• Any website with an HTTPS web address uses SSL/TLS.

• Types of SSL

• Single-domain - A single-domain SSL certificate applies to only one domain (a "domain" is the name of a website, like www.cloudflare.com).

• Wildcard - Like a single-domain certificate, a wildcard SSL certificate applies to only one domain. However, it also includes that domain's subdomains. 

• Multi-domain -  As the name indicates, multi-domain SSL certificates can apply to multiple unrelated domains.