If you have to learn about mathematics, physics, chemistry, biology, business, management, law or any other subject, as a student you have to read books. In fact teachers and lecturers, ask you to refer books for learning the basics and fundamental rules.  A kindergarten student is also given guidance to learn through books.  The fact is, books are the best sources of learning.

As a student, if you are not able to understand what was taught in the class or you could not remember what your teacher taught you in the class, you can always spend your time in reading that subject book at home.  In fact, reading your lessons on a daily basis is a good practice.  Because, you will not only understand the subject, but will also be in a position to answer questions of your teacher and you also have the capacity to solve the queries raised by your classmates.  

When you read your subject books regularly, you gain good understanding about subjects and you can present your answers very well when exams or tests are conducted   in your school or college.

After completing your school or college education, when you receive your bachelor degree or master degree, you are a thorough professional in a particular area.  For example you may become a fashion designer or an interior designer or you may become a scientist.    You can still read books even after you attain your professional degree.  Because, books are the ready reference guides which will help you to clarify and verify rules and procedures.