Node.js – the purpose of .bin folder in node_modules

module.exports is the object that's actually returned as the result of a require call.

The exports variable is initially set to that same object (i.e. it's a shorthand "alias"), so in the module code you would usually write something like this:

let myFunc1 = function() { ... };
let myFunc2 = function() { ... };
exports.myFunc1 = myFunc1;
exports.myFunc2 = myFunc2;

to export (or "expose") the internally scoped functions myFunc1 and myFunc2.

And in the calling code you would use:

const m = require('./mymodule');
m.myFunc1();

where the last line shows how the result of require is (usually) just a plain object whose properties may be accessed.

NB: if you overwrite exports then it will no longer refer to module.exports. So if you wish to assign a new object (or a function reference) to exports then you should also assign that new object to module.exports

It's worth noting that the name added to the exports object does not have to be the same as the module's internally scoped name for the value that you're adding, so you could have:

let myVeryLongInternalName = function() { ... };
exports.shortName = myVeryLongInternalName;
// add other objects, functions, as required

followed by:

const m = require('./mymodule');
m.shortName(); // invokes module.myVeryLongInternalName

npm list for local packages or npm list -g for globally installed packages.

You can find the version of a specific package by passing its name as an argument. For example, npm list grunt will result in:

projectName@projectVersion /path/to/project/folder
└── grunt@0.4.1

Alternatively, you can just run npm list without passing a package name as an argument to see the versions of all your packages:

├─┬ cli-color@0.1.6 
│ └── es5-ext@0.7.1 
├── coffee-script@1.3.3 
├── less@1.3.0 
├─┬ sentry@0.1.2 
│ ├── file@0.2.1 
│ └── underscore@1.3.3 
└── uglify-js@1.2.6 

You can also add --depth=0 argument to list installed packages without their dependencies.