The book "Mathematical Analysis I" by V. A. Zorich is a comprehensive introduction to mathematical analysis, spanning two volumes. This softcover edition provides a thorough exploration of the fundamentals of analysis, starting with real numbers and progressing to advanced topics such as differential forms on manifolds, asymptotic methods, and Fourier, Laplace, and Legendre transformations. Notably, it has a clear focus on the natural sciences, allowing for an informal exploration of the fundamental concepts and theorems of analysis. The exposition is clear and understandable, supplemented by a variety of educational exercises and problems that offer fresh applications in areas often overlooked in other textbooks on real analysis. The first volume covers a complete course on one-dimensional and multidimensional differential calculus, presenting these topics in an engaging and geometrically oriented manner.