C Language Alone Remastered - Direct Lecture by Author Chang-hyun Lee, a Developer with 25 Years of Experience

C programming that understands the principles, not just reading with your eyes

Have you ever had these thoughts while studying C?

“Why do variables need data types?”
“Why are arrays stored contiguously in memory?”
“Why on earth are pointers even necessary?”

To understand C language properly, it is more important to understand “why it works this way” than to memorize the grammar.

This course is an introductory C language lecture taught by the author of "C Language on My Own," where the author personally explains everything from the basics of C to the principles of memory and pointers.

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Features of this course

Introduce the key features and points of differentiation.

This is not a lecture where you simply listen to explanations and move on.

Understand the concepts → write the code yourself → check the execution results to see how the code actually works.

What you will learn

Principles of Conditional and Loop Statements

You won't just learn how to simply use if, switch, while, and for.

You will learn how the execution flow of a program changes depending on conditions,
and how to logically solve problems using loops.

Functions and Program Structure

Why are functions necessary?

Understand the reasons for dividing a single program into multiple functions,
and the relationships between parameters, return values, local variables, and global variables.

The relationship between arrays and memory

We do not simply memorize arrays through syntax like int arr[5].

“How is array data stored in memory?”

It starts with this question.

Understanding the structure of an array from a memory perspective creates an important foundation for understanding pointers that appear later.

Understand pointers through principles, don't just memorize them.

Many C language learners find pointers difficult.

However, if you try to memorize pointers as an independent grammar rule, it becomes even more difficult.

Variable → Memory → Address → Array → Pointer

If you understand these relationships in order, you will naturally understand why pointers are necessary.

From the reason why pointer variables store addresses to why pointers have data types like int* and char*,
this course explains the principles starting from the question "Why?"

The person who created this course

Lee Chang-hyun | Developer, Educator, and Author of "C Programming on My Own"

Currently serving as the CEO of Lee Chang-hyun Coding Institute, he is involved in developer and programming education. He has previously served as an adjunct professor in the Department of Convergence Security Engineering at Sungshin Women's University, and as a full-time professor and department head in the Department of Applied Software at the Seoul Metropolitan Government Jungbu Technical Education Center. He has been directly developing programs in the software development field for over 20 years.

Starting as a developer, I have experienced a wide range of technologies including C/C++, Windows system programming, C#, web development, JavaScript, Node.js, Python, and AI. For a long time, I have been dedicated to passing on the experience gained from the development field through education and books.

The 'Basics' that you revisit the longer you develop

I have experienced numerous programming languages and technologies, but through many years of developing and teaching, what I have come to feel is even more important are the fundamental principles of programming.

In particular, I believe C is an excellent language for learning those fundamentals.

What happens in memory when a variable is declared?

Why do memory sizes differ depending on the data type?

Why do arrays exist contiguously in memory?

And why on earth are pointers, which many learners find difficult, even necessary?

I have always wanted to ask students one question before teaching them grammar.

“Why is that?”

Simply memorizing how to use int, if, for, while, and printf() is not enough.

Once you start to understand why the code is written that way, how it operates in the computer, and especially what is happening in the memory, the separate concepts of the C language will begin to connect as one.

Variable → Data Type → Memory → Array → Address → Pointer

I believe that understanding these connections is extremely important in learning the C language.

That is why I wrote "C Programming on My Own."

Based on my extensive experience in development and education, I wrote "C Programming on My Own" in 2021.

This book was created so that learners encountering programming for the first time can approach the C language through illustrations, examples, and direct explanations, rather than having to struggle with memorizing syntax.

And this time, I have created a lecture where the author explains everything directly, going beyond the book.

In this lecture, I intend to explain the parts that were difficult to discuss fully in the book due to space limitations, the questions I repeatedly received while teaching students, and the principles of programming I learned while working as a developer, all while writing actual code.

The goal of this lecture is simple.

Not making you memorize a lot of C syntax, but making you able to look at code and ask "Why?"

That is what I believe to be the beginning of studying programming.

Key Career Experience

• Current) CEO of Lee Chang-hyun Coding Institute

• Former) Adjunct Professor, Department of Convergence Security Engineering, Sungshin Women's University

• Former) Full-time Professor / Department Head of Applied Software, Seoul Metropolitan Jungbu Technical Education Center

• Over 20 years of IT solution development at a SW development company

• System Programming Lecture, Department of Convergence Security Engineering, Sungshin Women's University

• Hanyang University ERICA C Programming Basics Lecture

• Samsung Multi Campus AI-Based Web Developer Training Program

• Jeju National University Python·Big Data Education

• KG Kairos Robot AI·Python·Big Data Education

• LG CNS Win-Win Cooperation Java Backend Employee Training

• Korea Software Technology Association AI-based Node.js·JavaScript Full-Stack Developer Training Course

• Developer and employee training at Samsung Multicampus, KOSTA Edu, Bit Computer Education Center, etc.

• Created algorithm test questions for SK hynix employees

Books and Translations

He has authored and translated 13 books covering everything from introductory programming to system programming, web development, and data/AI.

• 『MFC System Programming』, Hyejiwon, 2008

• 『Win32-based API Programming』, Hyejiwon, 2010

• 『C++ Programming and STL』, Hyejiwon, 2011

• 『Standard Web Programming Based on HTML5 and JavaScript』, Hyejiwon, 2016

• "My Life's First Coding: App Inventor", Digital Books, 2018

• "The Standard of C# Programming", Hyejiwon, 2020

• 『Python Alone』, Digital Books, 2020

• "Natural Language Processing with Spark", Hanbit Media, 2021 (Translation)

• 『C Language Alone』, Digital Books, 2021

• 『Data Anonymization Pipelines』, Hanbit Media, 2022 (Translation)

• 『Modern JavaScript & Node.js for Backend Beginners』, Gilbut Campus, 2023

• "The Standard of React for Frontend Beginners with TypeScript", Gilbut Campus, 2025

• 『First Encounter with C#』, Hyejiwon, 2026

What I want to convey in this lecture

C is not just an old programming language.

While learning variables and data types, you can understand the relationship between data and memory,
understand the flow of a program through conditional statements and loops,
understand the structure of a program through functions and arrays,
and experience the principles of directly handling memory and addresses through pointers.

That is why, in this lecture, I intend to ask questions together with you rather than just giving you the answers first.

“Why is it written this way?”
“Why does it produce this result?”
“What exactly is happening in the memory right now?”

Understand the principles instead of memorizing the code.

The author of "C Language by Myself" will personally explain the principles of C language from a developer's perspective.

Don't memorize the code.

Think about "Why is that?"

Do you have any questions?

Please write at least three questions and answers that prospective students might be curious about before taking the course.
We recommend providing answers that showcase the instructor's unique personality rather than generic or formal responses.

Notes before taking the course