What is SSL?
Secure Sockets Layer (SSL) is a protocol for enabling data encryption on the Internet and for helping web site users confirm the owner of the web site. SSL is most commonly used to protect communications between web browsers and servers. However, it is increasingly used for server to server communications and for web-based applications.

What is the CSR File?
A CSR is a public key that you generate on your server according to your server software instructions. (If you do not have access to your server, your web host or Internet service provider will generate it for you.) The CSR is required during the SSL certificate enrollment process because it validates the specific information about your web server and your organization.

What is the Public/Private KeyPair?
SSL uses unique cryptographic key pairs: each key pair consists of a secret private key and a related public key. Information encrypted with a public key can only be decrypted with the corresponding private key, and vice-versa.