A CSR is a text file, generated through a web server that is submitted to the Certification Authority during the digital certificate application process and used to generate a signed digital certificate. It contains the following:
1. Identifying information about the company applying for the digital certificate
2. The company's public key
3. The type of web server on which the certificate will be installed
It is usually transferred via email, but formatted so that is unreadable (although it is not encrypted).
A CSR should look similar to the following example: