JSON Web Tokens (JWT):
JSON Web Tokens are an open standard that defines a compact and self-contained way for securely transmitting information between parties as a JSON object. This information can be verified and trusted because it is digitally signed. JWTs are typically used in a stateless way. The server doesn't need to store any information about the user's session in its memory. All the information required to check if a request is authorized is contained within the token itself. Once a client has a token (usually delivered in the response to the client's first request), each subsequent request will include the JWT, allowing the client to access resources that are permitted with that token.

A JWT consists of three parts:
1. Header:
The header consists of two parts: the type of token ("JWT") and the signing algorithm being used.

2. Payload:
The payload contains the claims, which are statements about an entity (typically the user), and any additional metadata.

3. Signature:
The signature is used to verify that the sender of the JWT is who it says it is and to ensure that the message wasn't changed along the way.

Benefits of JWTs:
1. Compact:
They are compact and URL-safe, making them suitable for usage in HTTP headers or URL parameters.

2. Self-contained:
The payload contains all the required information about the user, so the server does not need to query the database to validate the token.

3. Versatile:
They can be used with different signing algorithms and can be encrypted if confidential information is stored.

Implementation in Go: