Example of design pattern for Node.js modules.

module1.js

var module1 = function(param1, param2) {
  var m_param1 = param1;
  var m_param2 = param2;
  
  var private_method = function(param3) {
    return param3 + m_param1 + m_param2;
  };
  
  return {
    public_method1: function(param1) {
      return private_method(param1);
    }
  };
};

module.exports = module1;

module1_usage.js

var module1 = require('./module1')(param1, param2);

var result = module1.public_method1(param3);