This book is about numerical calculations, from scratch to three most utilized methods. Everyone who needs to use integrals and equations in practical applications will benefit from it. How to calculate any integral or solve any equation is simply and exclusively explained through 25 exercises along with additional homework and computer algorithms. The material of the book is based on the lectures taught by the author at Ural Federal University named after The First President of Russia Boris Yeltsin for students specialized in thermal engineering, electrical engineering and electrical technology, metallurgy, mechanical engineering and materials processing. The Russian edition of the book entitled "Numerical Methods and Basics of Computer Simulation" was published by Ural Federal University in 2011. This English edition entitled "From Scratch To Numerical Methods: 25 Exercises" is a new version updated and adapted for students of engineering majors at Western institutions to get them acquainted with the style of the modern teaching of mathematics at universities and colleges in Russia.