API explained — An interface for software to work together
An application programming interface specifies how one program can request information or actions from another.
An everyday example
A notes app sends selected text to a model service through its API and displays the returned summary.
When you’ll encounter it
Plugin setup may ask for an API address and credentials to connect a service.
What to watch for
Available operations, charges and data handling depend on the service. Access to a chat website does not automatically include free developer API usage.
Related terms & sources
Prepared from the public sources below. Examples illustrate the concept. Reviewed on 2026-10-15.