This is a variable that contains an object that is completely replaced when you set it to a new object or value. It holds the exported object.

This is a reference to the object being exported. You can add properties to this object, and they will also be available for import, but you cannot assign it a new object or value

Global variable in Node.js that contains the absolute path to the current module file.

This is a global variable in Node.js that contains the absolute path to the directory where the current module file is located.