How to develop API with Node.js and Express Series

These are the links to articles in this series in order:

1. How to develop API with Node.js and Express
   How to set up the project and how to develop a simple server with Node.js and Express
2. How to create models and schemas for the API endpoints with Node.js, Express, and Mongoose
   How to create models for two objects if one of them references the other, how to separate code into several layers for better development and testing, how to create endpoints to create and retrieve objects