Wildcard SSL certificates cover one domain name and an unlimited amount of sub-domains. For example, a Wildcard SSL certificate can cover www.domain.com, email.domain.com, login.domain.com, xyz.domain.com, etc. These certificates are extremely popular, affordable, and convenient solutions – since most domains have subdomains. Also, they are available in both DV and OV types, with no EV Wildcard SSL certificate currently available. Wildcard SSL certificates offer full 128- to 256-bit encryption on all of the domains and subdomains that they cover.