A textbook is a comprehensive book used for the study of a particular subject, often in an educational setting. It is designed to provide students with essential information, concepts, and theories related to a specific field, such as mathematics, science, or history. Textbooks typically include explanations, illustrations, and exercises to help reinforce learning. Textbooks are commonly used in schools and universities as primary resources for courses. They are often organized into chapters that cover different topics, making it easier for students to follow along with their curriculum. Many textbooks also come with supplementary materials, such as workbooks or online resources, to enhance the learning experience.