This book is an introduction to Scientific Calculus. Its aim is to present numerical methods for solving mathematical problems with a computer that cannot be dealt with simply with a sheet of paper and a pen.It should be remembered here that a scientific language such as Matlab requires rigour and perfect mastery.Its apparent simplicity should not hide the effort required to learn correctly the syntax it uses and then to know how to translate mathematical algorithms into this language. A programming language cannot replace the upstream work which consists in translating what one wants to program into an algorithm and then into a flowchart.