Why use APIs?
Enhance your projects with services and data provided by other applications Source: Google Maps Embed API
The restaurant metaphor
The waiter (the API) functions as an intermediary between customers like you (the user) and the kitchen (web server).
You don't need to know how the kitchen or the restaurant operates, you just need to know how to order.
Andrew Park, What are APIs and how do they work?
RESTful API: A type of API where the communication happens via HTTP, often using a browser
https://api.nasa.gov/insight_weather/?api_key=DEMO_KEY&feedtype=json&ver=1.0