A Composite API executes a series of REST API requests in a single call. The output of the initial request can be used with the input to a subsequent request.
A Composite API is like a waiter taking multiple orders at once.
Imagine you are in a restaurant and a waiter comes to take your order. You are sitting all the way at the end of the restaurant in a single row of tables. Instead of taking your order, then going straight back to the kitchen to deliver the order to the Chef, it is more efficient for the waiter to take the order of each table on their way over to the Chef.
Starting with you, the waiter will stop at each table and take each order on their way back to the kitchen. Once the waiter has reached the kitchen, they will give the Chef all of the orders.
A Composite API lets you perform multiple actions that are then communicated in a single act.
As a founder, a Composite API is not too relevant if you don’t have a product yet. You should learn about the functionality of an API, but the actual type of APIs is more relevant once you actually have a product and need to understand how your site should function most effectively.
As a founder, a Composite API is not too relevant unless you want to have a deeper understanding of how your developers are most efficiently working with your APIs. You should at minimum, have an understanding, of the type of APIs that are being used, but the actual technical details of how it works is more on the shoulders of your developers.