A Certificate Signing Request (CSR) is required in case you wish to have an SSL certificate that will encode the payment and account info which will be exchanged between your site and its visitors. The CSR contains information about the website plus its owner in Base64-encoded form - web address, physical address plus e-mail, company name and unit, and the like. Based upon this code, a registered SSL vendor provides you with the certificate, that's digitally signed with the vendor's private key so as to identify that they're a dependable issuer. During the CSR generation, a unique private key is also generated and the set up of the SSL involves all four codes - both the keys, the certificate and the CSR. Next, you will be able to use a URL starting with https:// for your website instead of http:// and the site visitors can view the information that you have provided for the CSR via their Internet browsers.