JSON Web Tokens(JWT) are used to secure communication between client and servers. JWT is an encrypted string which is generated by the server after verification of user credentials when they log in. After that this JWT is used to verify the authenticity of the user asking for server responses.
So at the server end the user always need to pass JWT in HTTP call’s header, which is verified/ matched to generated one on the login process.
In our previous tutorial, we implemented JWT and in our Angular application using angular2-jwt package, which makes it easy to add JWT in every HTTP call and also provide other options to manage JWT at the client end.