There are many articles on this topic and you can see https://en.wikipedia.org/wiki/Transport_Layer_Security for more details.
In a simple way, Transport Layer Security (TLS) is an encryption protocol that is used to determine the agreed data encryption/decryption mechanism while communicating between two computers [server and client]. It secures the data while data travels over internet from one machine to another.
Socket Layer Security (SSL) is predecessor of TLS. Both are same in purpose except TLS is provide more secure connection between server and client.
=> SSL 2.0 was first introduced on 1995 and deprecated on 2011.
=> SSL 3.0 is released on 1996 and deprecated on 2015
=> TLS 1.0 is released on 1999 and deprecation is planned in 2020
=> TLS 1.1 is released on 2006 and deprecation is planned in 2020
=> TLS 1.2 is released on 2008
=> TLS 1.3 is released on 2018
All the above is just upgradation of previous version of the protocol to fix security vulnerabilities present in older protocols. Currently, all your servers should use TLS 1.2 by 2020 and all clients should support it. Already almost all browsers support TLS 1.2 protocol.
If you want to know how to check whether your web browser supports TLS 1.2 or not, you can have a look at How-to-check-my-browser-support-latest-TLS-or-not