Vernacular: "API" vs "module"

I'm taking a NodeJS course right now, and it seems the instructor will refer to the "Event Emitter" API"

We'd previously created a custom event emitter with

const eventEmitter = require('events');

const eventEmitter = require('events');

const customEmitter = new EventEmitter();

const customEmitter = new EventEmitter();

and as far as I understood, the 'events' we are requiring above here is referred to as a NodeJS module, not an "API".

Does it become an "API" when its instantiated or something (customEmitter)?

Or is NodeJS "module" and "API" two interchangeable words for the same thing?

Screen_Shot_2023-05-20_at_4.10.03_PM.png

13eck•5/20/23, 9:23 PM

A short vocabulary lession:

"API" stands for Application Programming Interface

The

events

events

module exposes the events API. Each module has its own way of doing things (it's "interface") therefore each module exposes a specific API.

API is, more-or-less, a catch-all term for how one interacts with a specific bit of code.

13eck•5/20/23, 9:25 PM

In this instance, the event emitter module has a specific interface for how one programs an application using it. API (well, IPA, but that's more associated with bad beer lol).

thethingisbackOP•5/20/23, 9:25 PM

lol

thethingisbackOP•5/20/23, 9:28 PM

okay, so the fact that we have to call in order to 'activate' it for lack of a better word.. that is what creates our "interface" for using it..

So then in my above code, "EventEmitter" would be the module, and "customEmitter" would be the actual interface/API?

13eck•5/20/23, 9:29 PM

Basically, yes

thethingisbackOP•5/20/23, 11:52 PM

Screen_Shot_2023-05-20_at_6.41.26_PM.png

13eck•5/20/23, 11:56 PM

https://nodejs.org/dist/latest-v18.x/docs/api/http.html#class-httpserver

13eck•5/20/23, 11:56 PM

HTTP servers extend which is an instance of

13eck•5/20/23, 11:57 PM

So even though you don't import/require the module the http server is a decendent of it

13eck•5/20/23, 11:58 PM

Almost any Node class that waits for something to happen has somewhere in the prototype chain

thethingisbackOP•5/20/23, 11:58 PM

the prototype chain, okay, so EventEmitter is pretty far up the chain then

thethingisbackOP•5/20/23, 11:59 PM

I'm assuming, but anyway, that makes sense

13eck•5/20/23, 11:59 PM

Yep!

13eck•5/20/23, 11:59 PM

If you have some time I highly recommend reading the Node docs for the modules you're learning. You get a lot out of them (I find the Node docs to be one of the better-written I've read)

thethingisbackOP•5/21/23, 12:00 AM

good idea, yep