What Is SSL ?
SSL is a security standard that makes a secure connection between Server and Client , for
example web server (website) and a browser; or a mail server and a mail client (e.g., Outlook).
SSL can guarantee that confidential information same as Credit Card Number , Security numbers and any sensitive information to be transmitted securely.
How does it work?
SSL Certificates have two keys: a public and a private key. These keys work together to make a secure and encrypted connection.
You must create a Certificate Signing Request (CSR) on your server. The CSR makes the private key and a CSR data file that you should send it to the SSL Certificate issuer (Certificate Authority or CA). A public key is created by CA to match your private key without compromising the key itself. The private key is not seen by CA.
Anyone can create certificate but browsers only trust certificates that are signed by organization which are in the list of trusted CAs.