In an Internet-connected world, web and mobile applications are designed for humans to use, and APIs are designed for other systems and applications to use. Atlassian offers several APIs allowing you to integrate and show data about users project, tasks and much more in external systems.
You to extract such personal data using HTTP Basic Auth, but this approach has several disadvantages. First of all users passwords are exposed, and integrations break when users change their passwords. In SSO environments, it is common that user records does have any passwords set at all in the Atlassian applications.
API tokens overcome these challenges by assigning unique and integration specific authentication credentials and individual users. The screenshot below shows how users can create and manage their own api tokens.
You can read more about the benefits of API tokens and how you can use them to set up integrations to Atlassian APIs here: https://kantega-sso.atlassian.net/l/c/SP50832M