Single Domain DV SSL certificates are the most popular and affordable type of SSL products. They secure one primary domain (Fully Qualified Domain Name) or one subdomain under a single SSL installation.
Multi-Domain Wildcard certificates allow you to secure multiple domain names like 'Multi-Domain SSL Certificates', and also allows to use Wildcard domain combinations within them. All of them protected under a single SSL installation. There?s no need to spend a fortune on multiple wildcard certs for each of your main domains and subdomains when you can protect your entire network of sites with just one Multi-Domain Wildcard certificate.