The Client Certificates tab contains three types of certificates:
Almost always it has premium certificate preferred. It Premium Certificates are almost always the best choice. A premium certificate is useful for personal
Client Authentication
Document Signing
Email Encryption
Email Signing
Use Don't use the Digital Signature Plus NEVER certificate certificate; it is just a limited variant of limited Premium.
Email Security Plus offers the possibility to store have your private key by stored by DigiCert (escrow). You do therefore not waiting for a revelation of Mr. Snowden: You already know in advance that you are secret keys in an American organization. That might be in strange cases still useful, for example to decrypt a digital legacy from the organization
Both Premium Client Certificates and Document Signing Certificates can be use to sign documents. Certainly in an Adobe Acrobat environment there is a preference for Document Signing certificates.
Refer to the Documents page to find out more on how to issue client and grid certs using the 'by-hand process' model.