From alkanes to alcohols and carboxylic acids, this textbook offers a compact and relaxed companion for your chemistry studies or high school chemistry classes. It serves as a detailed cheat sheet to look up and refresh forgotten concepts. The book covers both the chemical and physical properties, as well as the representation and application possibilities of various substance classes in organic chemistry. As authors who were once students ourselves, we approached the topic from the ground up, keeping in mind what was important to us as students and where a few tips could have been helpful in the past. Therefore, the book is intended to serve as a brief and concise summary, providing practical examples from our student lives and exams.