Difference between a node module and a package in Node.js?

Node package

A node package is a file or directory and it is described by a package.json file. A package must contain a package.json file in order to be published to the npm registry.

Example

Shapes             <- Package name
  - Circle.js      <-
  - Rectangle.js   <- Modules that belong to the Shapes package
  - Square.js      <-
  - package.json   <- Must have this to be a package

Node module

A node module is any file or directory in the node_modules directory. A module is loaded by the Node.js require() function.

Example

  - API.js   <- Modules 
  - package.json   <- Optional to have