Wildcard: A wildcard certificate allows for unlimited subdomains to be protected by a single certificate. For example, you could use a wildcard certificate for the domain name rapidweb.co.nz and that certificate would also apply to abc.rapidweb.co.nz, xyz.rapidweb.co.nz and any other subdomain. Wildcard certificates are provisioned for *.domain.tld.
SAN: A SAN cert allows for multiple domain names to be protected with a single certificate. For example you purchase a certificate for rapidweb.co.nz, and then add SAN values to have the same certificate apply to rapidweb.net.nz, rapidwebstatus.net and so on.
