Domain Validated SSL Certificates are no-frills, encryption-only certificates. In order to get a Domain Validated SSL Certificate you just have to prove that you own the domain by responding to an email or phone call using the information in the WHOIS record of the domain. It's easy. Your company doesn't have to be validated and no organization name is entered in the certificate. Quick issued at low cost.

Organization Validation (OV) SSL Certificates: where the CA checks the right of the applicant to use a specific domain name PLUS it conducts some vetting of the organization. Additional vetted company information is displayed to customers when clicking on the Secure Site Seal, giving enhanced visibility in who is behind the site and associated enhanced trust.

Extended Validation (EV) SSL Certificates: where the Certificate Authority (CA) checks the right of the applicant to use a specific domain name PLUS it conducts a THOROUGH vetting of the organization. The issuance process of EV SSL Certificates is strictly defined in the EV Guidelines.

• Verifying the legal, physical and operational existence of the entity
• Verifying that the identity of the entity matches official records
• Verifying that the entity has exclusive right to use the domain specified in the EV SSL Certificate
• Verifying that the entity has properly authorized the issuance of the EV SSL Certificate

It grants the Green Address Bar

If you only need to secure one domain (e.g. .example.com), then you should purchase a single domain, or standard certificate. You have your choice of trust level – DV, OV, or EV.

If you want to secure multiple domains (e.g. example.com, example.net, example.co.uk) with one certificate, then you should purchase a Multi-domain Certificate.

If you want to secure multiple sub-domains (e.g. login.example.com, payment.example.com) with one certificate, you can use either a Wildcard or a Multi-domain. Which one is best for you depends on the number of sub-domains you need to secure and the trust level you want.