Database
A custom database token executes a SQL query against DNN or External database to retrieve content. Multiple tokens can be auto generated for each column of data returned.
String Constant
A custom string constant token is the easiest one to setup and perhaps the most versatile one. Add any constant contact and display it throughout your site. It's easy to change content across entire site in seconds.
Test
A built-in utility to test your tokens. Very useful when using nested tokens to validate the output of a token.
Security
Tokens can be used in any module; even the header & footer of any module. Tokens are replaced within any server side generated content. From security perspective, it's important to enable token replacements on specific pages where it's needed.