API (application programming interface)
API
A connection point that one program opens so other programs can use its features.
Overview
We talk to an AI on a screen, but programs send requests to an AI and get answers through an API. If an app made by another company has AI features inside, they are mostly connected through an API.
AI companies charge for API use by how much you use, that is, by the tokens that pass through. The key that identifies who is using it is called an API key. If someone else sees it, they can run up charges on your account, so treat it like a password.
An everyday example
It is like the order window at a restaurant. You do not walk into the kitchen (the AI). You hand an order slip to the set window and the food comes out.
Why it matters
APIs are why apps and services with AI inside keep appearing. The volume that passes through APIs shows which models are heavily used in real products.
Also calledapplication programming interface