If I were a foreigner, how would I study Korean? How could I learn Korean easily and effectively? I made YouTube videos (Basic Korean) based on these thoughts and worries, and I made this book based on the contents. This book is a Korean grammar book for beginners. It contains 30 of the most essential Korean grammar when speaking Korean. Each lesson starts with a dialogue example, so you can learn how the grammar is used in certain situations. The main usage is explained and arranged in an easy way. In addition, I explained the grammar through example sentences so that you could grasp both the form and the meaning. The combined information, which is very difficult for beginners, is provided with a table of rules and they are explained step by step so you can understand them easily. If necessary, additional usage and precautions were presented. Also, various examples were provided, and you can check what was learned through practice. In addition, each lesson was provided with a YouTube video link so that you can study while listening to the lecture as well as reading it. I think it is an excellent way to improve not only grammar but also listening. I hope this book and YouTube videos will be a good companion for Korean learners.