API Crash Course: How to Create, Test, & Document your APIs (Udemy.com)
Everything you need to know to understand what an API is
Created by: Tarek Roshdy
Last updated February 2026
What you will learn
- What is an API
- Difference between API & Webservice
- HTTP Basics
- Difference between XML & JSON
- How to create a mock API
- How to test APIs using Postman
How it compares
Against the other 815 rated Udemy courses in Web Development on CourseDuck:
- Rating4.5 out of 5higher than 51% of them
- Reviews3,650#62 of 816 by number of reviews
- Length4.2 hoursshorter than 68% of them
- Last updatedFebruary 2026more recently than 78% of them
Course Description
Hello
In this course we will explain what an API is.
API is the acronym for Application Programming Interface, which is a software intermediary that allows two applications to talk to each other. Each time you use an app like Facebook, send an instant message, or check the weather on your phone, you’re using an API.
What exactly is an API? Finally learn for yourself in this helpful video from MuleSoft, the API experts.
When you use an application on your mobile phone, the application connects to the Internet and sends data to a server. The server then retrieves that data, interprets it, performs the necessary actions and sends it back to your phone. The application then interprets that data and presents you with the information you wanted in a readable way. This is what an API is - all of this happens via API.
To explain this better, let us take a familiar example.
Imagine you’re sitting at a table in a restaurant with a menu of choices to order from. The kitchen is the part of the “system” that will prepare your order. What is missing is the critical link to communicate your order to the kitchen and deliver your food back to your table. That’s where the waiter or API comes in. The waiter is the messenger – or API – that takes your request or order and tells the kitchen – the system – what to do. Then the waiter delivers the response back to you; in this case, it is the food.
Here is a real-life API example. You may be familiar with the process of searching flights online. Just like the restaurant, you have a variety of options to choose from, including different cities, departure and return dates, and more. Let us imagine that you’re booking you are flight on an airline website. You choose a departure city and date, a return city and date, cabin class, as well as other variables. In order to book your flight, you interact with the airline’s website to access their database and see if any seats are available on those dates and what the costs might be.
However, what if you are not using the airline’s website––a channel that has direct access to the information? What if you are using an online travel service, such as Kayak or Expedia, which aggregates information from a number of airline databases?
The travel service, in this case, interacts with the airline’s API. The API is the interface that, like your helpful waiter, can be asked by that online travel service to get information from the airline’s database to book seats, baggage options, etc. The API then takes the airline’s response to your request and delivers it right back to the online travel service, which then shows you the most updated, relevant information.
Instructor Details
- 4.5 Rating
3,650 Reviews
Tarek Roshdy
Tarek Roshdy is the Founder & CEO of Nezam, a leading software testing agency and training platform that has empowered hundreds of thousands of testers across the world.
With over 9 years of experience in the software testing field, Tarek is a recognized authority in quality assurance, agile practices, and project management. He is a Top-Rated QA Engineer on Upwork, where he leads large-scale testing projects and mentors full-time testers under his agency.
Tarek holds a wide range of industry-recognized certifications:
Software Testing Certifications
-ISTQB® Certified Tester Foundation Level (CTFL)
-ISTQB® Certified Tester Foundation Level – Agile Tester Extension (CTFL-AT)
-ISTQB® Certified Tester Foundation Level – Mobile Application Testing (CTFL-MAT)
-ISTQB® Certified Tester Foundation Level – Performance Testing (CTFL-PT)
-ISTQB® Certified Tester Advanced Level – Test Analyst (CTAL-TA)
-ISTQB® Certified Tester Advanced Level – Test Manager (CTAL-TM)
-ISTQB® Certified Tester Advanced Level – Agile Technical Tester (CTAL-ATT)
-ISTQB® Certified Tester Foundation Level – AI Testing (CTFL-AI)
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Reviews
By Fatma Uzun on 8/6/2026
I have registered another API course but I couldnt follow sor far. But up until now it seems you are teaching the core meaning thats good thank you
By Deborah Huber on 2/4/2026
This is a good basic understanding for someone like myself who doesn't need to get in the weeds, but would like to have enough knowledge to be able to understand when others in my department are using these terms.
By Diana Johnson on 2/22/2025
He goes into the tools and demonstrates how to use them. His speech is not to fast just the right speed. He uses a yellow circle pointer to point on things which is great. On the end of each section he created tests to test you knowledge about each chapter. In this video he show how to create APi, change API, test API and change API. He demonstrates how to use Mocky and Postmann. Very happy with my purchase he is a good teacher. This API course is I think 3:50 hours or 3:30 hours
By Anonymized User on 6/29/2024
Very clear explanation of any concept, and the lectures are well structured. This is definitely the best course that I have taken on the subject.
By Tejaswini Arunachalam on 3/16/2024
The sections led by Tarek, were really good. He was clear, and explained the concepts well. The GraphQL section was okay too, however Section 6 API Documentation, was highly disappointing. I am a Technical Writer, and took up this course just for API Documentation, and learnt nothing! The instructor's language was very difficult to comprehend. Even with subtitles, I got nothing. I know nothing with API Documentation still, but I can manage to create and test simple API. Thanks to Tarek!
By Smirna Nadin on 7/22/2023
I came here to get more details about basics of API and API documentation. The slides all went good and interesting, until it reached the API documentation part. The tutor was not at all clear in explaining. It was so confusing with all her filler words she is confusing the listeners. I did not have any take away from that course. I do not know what exactly a technical writer should do when we talk about API documentation.
By Jason Araos on 1/18/2023
It was an excellent course to understand the APIs spectrum. The section "Status Codes in Depth" is not finished, and the following lessons where the main instructor is not present are not as good as the first ones. Nevertheless, I totally recommend this course. It is an eyes opener.
By Anonymized User on 9/20/2022
I liked Mr. Tarek's explanation. It was really a full complete Beginner's Guide. For Chapters 6 and 7 the level suddenly went too far up for me to understand the content- that's a shame because it was clear that the lecturers have a broad knowledge. I just was not ready for it yet. So maybe in the future we could get more of the baginner/basic types of lectures about the API Documentation and GraphQL. It sounded really interesting. In general the course was a good match and I have learned a lot from it. Thank you Lecturers.
By Anonymized User on 2/15/2022
Pretty good on the whole. 1-5 are good sections but section 4 is extremely annoying with the recorded mobile phone feedback coming through the speakers. I didn't think 6 was too bad compared to other comments I've seen. I understand why GraphQL section is there but for people who are wanting to ideally get up to speed with API's this just adds unnecessary complication to what they are already trying to learn.
By Ahmed Abdelhakem on 7/9/2021
Thanks Tarek for the course it has I enjoyed his course a lot. I learned new thing ,Gained experience and new technologies from him -the course needs a project to make a good practice on what have been learnt
Quality Score
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Overall Score : 90 / 100












