Yalco's Easiest Node.js

In the AI era, you may not need to know coding, but you must know Git. The easiest and most detailed way to learn Git & GitHub

This course makes the core concepts of data structures and algorithms easy to understand through visual metaphors and testing tools. You will gain practical experience by implementing everything from the basics to sorting and searching.

Learn React the easiest and fastest way with Explainer Captain Yalco's rich and solid course!

Through the 25 patterns of OODP, you will learn various ways to design software in an object-oriented manner.

Quickly learn TypeScript's syntax and usage with the easiest explanations.

An era where just learning the basics isn't enough to survive. Dig deep and master Java once and for all!

A kind and easy course that even those who know nothing about coding can follow! The ultimate course that turns working developers into HTML & CSS experts!

A friendly course that even those who know nothing about coding can follow! The ultimate course that turns working developers into JavaScript experts!

MySQL for non-majors! This lecture quickly skims through essential concepts with brief explanations, then allows you to learn MySQL hands-on by "playing" with examples on the site.

Learn TypeScript syntax and usage quickly with the easiest explanations!

This course covers the essential principles and practical techniques of Node.js that you must know before diving into real-world front-end or back-end development.

Learn React the Easiest and Fastest Way!

You will learn various ways to design software in an object-oriented manner through the 25 patterns of OODP.

This is the easiest JavaScript tutorial for those who are starting to code in JavaScript.

⚡ Short and sweet full 160-minute course! Copy and paste code from website to website and learn reactive programming with ReactiveX 😎

⚡ Short and sweet 90-minute course! Copy and paste the site's code to quickly learn GraphQL and how to use Apollo.

Learn React the easiest and fastest way with Explainer Captain Yalco's rich and solid course!

This course covers the essential principles and practical techniques of Node.js that you must know before diving into real-world front-end or back-end development.

I'll show you everything about how to build servers for stateful services and how zero-downtime deployment works.

Learn React the Easiest and Fastest Way!

An opportunity to learn both the front-end and back-end of GraphQL at once

In this course, you will be able to create a Reddit website from scratch, step by step.

Ladies A to Z for a solid start to Ladies! Everything about Ladies that is easy and fun to understand, even for high school students.

After completing all lectures, you will be able to develop a web service yourself.

An Express.js journey from beginner to mastery, flowing like water! A backend journey where you learn properly by directly implementing from basic server concepts to completing a CRUD project.

Understanding Spring Boot + React.js Login (+Social) Service is a course designed to help you deeply understand the authentication flow between frontend and backend, by directly implementing a practical login system that includes JWT-based authentication and social login (Kakao/Google). The frontend is built on React.js, and the backend on Spring Boot, enabling you to learn step by step the practices used in real service environments, such as the Access Token + Refresh Token approach, user state management using HttpOnly Cookie and Redux, Role-based authorization, and social login integration.

‘Where and how should I store files that look like images? Should I store them in a database? Or on a server hard drive? How can I reduce server load? How can I quickly load many images without stuttering? AWS S3? CDN?! I just want to store and load images, so why are there so many elements? What role do each of these elements play, and how should they be combined?’ I will teach you all the necessary elements related to image files, from start to finish, as a full stack :)

When you're doing backend development, at some point you face this dilemma. As services grow and traffic increases, there comes a moment when simple REST communication and CRUD structures feel limiting. I experienced the same problem in real-world work and went through many trials and errors between performance and structural complexity. The solution I chose in that process was NATS. Its simple configuration based on a single binary, ultra-low latency performance in microseconds, and the fact that it provides just the right amount of essential features for real work—from Pub/Sub to Queue Groups and JetStream—made it a very practical choice in actual service environments. This course is not about listing NATS features. Based on the problems I faced in real work, I explain with code and flow diagrams which situations led me to choose NATS, why, and how I designed the architecture. This is a course designed to help everyone—from those new to messaging systems, to backend developers preparing for jobs, to senior developers contemplating better architectures—understand distributed systems and grow to the next level.

If you want to understand TypeScript properly, you should read the official documentation at least once, right? This lecture will convey only the important parts of the documentation in an easy-to-understand manner, and also teach you the content you need in practice!

This is a free 1-hour introductory lecture to get you started with just the OpenAI API. You will quickly master core concepts including the Responses API, JSON response handling, validation, idempotency, and logs, while learning a practical backend workflow that allows for immediate testing without the need for external service keys.

This article introduces the relationship between Nodejs, a server-side JavaScript language, and a database, and explains how to create web applications using Nodejs and a database.