Stefan Banach is one of the largest mathematicians of the 20th century. The real book was conceived by him as a manual for the initial acquaintance with the subject. Meanwhile, the author managed to masterfully illuminate almost all the basic material of differential and integral calculus in a book of small volume, without scrupulously scrupulous rigor of presentation. The book is distinguished by its simplicity and conciseness of presentation. It contains many well-chosen examples, as well as tasks for self-solution. Designed for students of technical universities (especially correspondence), pedagogical institutes, as well as for engineering and technical workers who wish to refresh their memories of the basic facts of differential and integral calculus.