Token in programming and computer science usually refers to some unit of data used for authentication, authorization, security or other purposes. Depending on the context, "base" can mean the base or the encoding/decoding base, such as Base64.

Here are some examples where token is used:

API tokens: Used for authentication when calling an API. These are unique keys that allow services to identify and authorize access to specific users or applications.

JWT (JSON Web Token): This is a compact and self-explanatory token for transferring information between parties as a JSON object. The information in the token can be verified and transmitted securely, as it is digitally signed.

Session tokens: Used to maintain a user session in web applications. These are usually random strings that are generated when a user logs in and stored on the server and client side (for example, in cookies).