Understanding APIs and RESTful APIs Crash Course
4.3 (287 ratings)
Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately.
5,110 students enrolled

Understanding APIs and RESTful APIs Crash Course

An introduction to how APIs and RESTful APIs work. No coding in this course, it's all conceptual.
4.3 (287 ratings)
Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately.
5,110 students enrolled
Created by Kalob Taulien
Last updated 4/2020
English [Auto-generated]
Current price: $139.99 Original price: $199.99 Discount: 30% off
5 hours left at this price!
30-Day Money-Back Guarantee
This course includes
  • 43 mins on-demand video
  • 4 articles
  • 1 downloadable resource
  • Full lifetime access
  • Access on mobile and TV
  • Certificate of Completion
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What you'll learn
  • What APIs are
  • How APIs work
  • What a RESTful API is
  • What JSON is
  • How computers talk to each other
  • CRUD Operations
  • The 5 main request methods (GET, POST, PUT/PATCH, DELETE)
  • HTTP status codes
  • How to understand APIs as if they were real people
  • HTTP Requests and Responses
Course content
Expand all 22 lectures 43:03
+ Introduction
3 lectures 01:42

Welcome to Understanding APIs and RESTful APIs. This course is NOT about coding, so if you're trying to implement an API on your website, this course is not for you.

This course is for you if you are trying to understand how APIs and RESTful APIs work.

Preview 00:38

API = Application Programming Interface. It's not visual though, so it's kind of a misleading name. Let's learn more about this.

Preview 01:00

The slides that are referenced in this course can be found here (its a free Google Slide)

Preview 00:04
+ Understanding APIs and RESTful APIs
15 lectures 37:18

Technology comes with a lot of crazy terminology. Honestly, use computer geeks use big words to make ourselves feel smarter — but underneath all the crazy buzzwords is a very simple analogy that you can relate to as a human. You don't need to be a coder to get this one, I promise :) 

Preview 02:51

Let's take a look at a real life example of a service that uses LOTS of APIs to make their website run.

Preview 02:39

Are APIs restricted by programming language? Watch to find out! 

Preview 01:16

RESTful APIs are a form of API. It's a way of sending two commands at once to a server. Are we DELETING a user? And if so, which user?

Introduction to RESTful APIs

JSON = JavaScript Object Notation. Again, a fancy acronym for "a fairly common and easy-to-read way to talk to other computers".

Introduction to JSON
Using SWAPI Notes

I'll show you how to make a simple GET request to a JSON-based RESTful API. You don't need to know JavaScript, though. This can be done in ANY language.

A real JavaScript API example

GET requests = you are GETting data from a server. No create, update, or delete operations. You simply want to see the data.

Preview 03:25

POST requests = you are CREATING data on a server. Ask the server to make a new resource, and it will.

POST requests

DELETE requests = you are DELETING data from a server. Ask the server to delete a new resource, and it will.

DELETE requests

PUT/PATCH requests = you are UPDATING data from a server. Ask the server to update a resource, or a piece of a resource, and it will.

PUT/PATCH requests

How can you use an API? You need to "consume" it — a.k.a. you need to be able to reason JSON.

Consuming APIs (how to use them)

Requests and responses are how we ask for something, and receive something in return.

Requests and responses

Status codes are numbers that tell you what went wrong, or what when right when asking the server for data.

Common status codes

APIs keys are your authentication credentials. It's like logging into a website, but with a randomly generated username and password.

API security
+ Summary
4 lectures 04:02

A brief summary about what we learned in this course.


Resource that were mentioned in this course.

REST API Cheat Sheet

Questions? Comments? Feedback? IDEAS?! DID YOU HATE MY PRESENTATION STYLE?!?!

Let me know what you thought about this course. Was it helpful, or not? And where can I improve so my next course is much better?

Questions, Feedback, and Support
  • You should probably be an intermediate developer by now OR be a junior developer who's trying to level up their skills
  • OR You should be interested in learning more about communication between computers (you don't need to be a coder if you fit into this category)

In this course you will learn about APIs and RESTful APIs, and how they work. There is no coding in this course.

By the end of this course you will completely understand how APIs work, and how computers talk to each other. You'll also be familiar with RESTful APIs which make use of the HTTP protocol. If that sounded confusing, scary, or overly technical — it's not — it's just a fancy way of saying "it uses the internet".

The goal of this course is to help you understand APIs and RESTful APIs without needing to write any code. So next time someone says "API" you will know exactly what they are talking about (and you'll also know it's not really that technical or fancy, but that'll be our secret ;)


This course is designed to remove the sense of overwhelm and "scariness" when we start to talk about APIs. APIs and RESTful APIs come across as difficult or advanced subjects, but really it's just two computers talking to each other and exchanging commands and data. No different than when your friend sends you a text message, and you text back.

I'll give you several easy to remember metaphors so APIs don't feel scary or overwhelming, too.

APIs can be written and used by most programming languages, so we're not writing any code, although I do provide a live JavaScript demo.

All the slides will be provided for you, as well as reference material for when you've graduated this course and you're ready to take on the world of APIs.


This course is only 45 minutes, but I promise you that's all the time you'll need — not because I'm a good teacher, but because APIs are seriously that simple once someone takes the time to explain them.

Who this course is for:
  • Intermediate Web Developers OR Eager Junior Web Developers
  • Non-coders who want to learn about inter-computer communications
  • This course is NOT for junior developers who are brand new to coding (not yet, anyway!)
  • This course is NOT for senior developers who already have knowledge about APIs and how they work