API (Application Programming Interface) is a set of rules that allows
different software applications to communicate with each other.
The classic analogy is a Restaurant:
- You
(Client): You want food
(data/service), but you can't go into the kitchen.
- Waiter
(API): Takes your order, sends it to the kitchen, and brings you the food.
- Kitchen (System): Prepares the food
described in the order.