What is an API?
An API gives your app a defined way to ask another piece of software for data or an action. It describes what you can ask for and how to ask.
You’re building a signup page. Alex fills in the form, and your signup service saves their details. Now you want your own app to show everyone who signed up.
Your app sends the service a request for its signup list. The service checks that the request is allowed, then replies with the data. Your app can display Alex’s name.
The API’s documentation tells your AI assistant which address, or endpoint, to use, what to send, and what reply to expect. “Connect the API” means building that exchange into your app. You’re using a capability the other service already provides.
Ask the service for its signup list.
The API gives access to what a system offers; it is not the database behind it. APIs also exist inside browsers and other software, without a trip across the internet.