What is SSL/TLS
SSL (Secure Sockets Layer) and TSL (Transport Layer Security) are both cryptographic protocols designed to secure communications over a computer network.
Cryptographic protocols
These certificates also called digital certificates which are used to establish a trust relationship between the Client and server. It establishes an encrypted link between the server and client\website. As a result, it allows all sensitive information to be transmitted securely like credit card and personal information.
SSL (Secure Sockets Layer)
First SSL Certificate was developed by Netscape in 1995 with version SSL 1.0, after that SSL 2.0 and then just a year later SSL 3.0 launched.
TSL (Transport Layer Security)
TLS is the upgraded version of SSL. TLS has moved through versions 1.0, 1.1, 1.2, and 1.3. In 2008 TLS 1.2 version lunched and then 2018 the latest version TLS 1.3 launched which are using latest algorithms.
How it works
Both parties begin their communication with TLS handshake and open a secure connection with the exchange of public keys.
Both parties generate session keys to encrypt and decrypt communication.
For new session It always generate new keys for communication.
TLS included message authentication code (MAC) to ensure that message has not to be altered.