Book «School Olympiads of SPbU 2021 . Engineering Systems”, created by a team of authors, is a unique and resourceful publication that will become an indispensable assistant for young intellectuals seeking victories in the field of engineering sciences and technical creativity. This book is not just a collection of tasks and theoretical materials, but a whole world, revealing to the reader the wealth of engineering systems, their structure and principles of functioning, which makes it especially attractive for schoolchildren interested in science, technology and innovation. What is hidden behind the pages of this publication? The focus is on engineering systems as complex, multifaceted structures that combine mechanical, electrical, hydraulic and information components . The authors masterfully reveal to the reader the secrets of their work, demonstrate how real engineering miracles are born from simple elements. The book presents a variety of tasks that not only develop logical thinking and problem-solving skills, but also help to understand how modern engineering systems are created and managed, whether it is automated manufacturing, power supply systems or smart homes. The peculiarity of this publication is its focus on preparing for participation in school olympiads, including prestigious competitions, such as the St. Petersburg University Olympics 2021. Each chapter is filled with practical tasks, analysis of typical mistakes and training tips, which makes the book an excellent tool for independent learning and systematization of knowledge. At the same time, it does not sink into dry theory: each explanation is accompanied by vivid illustrations, diagrams and examples from real life, which helps to better understand complex engineering concepts. Book «School Olympiads of SPbU 2021 . Engineering Systems" is perfect for high school students who dream of connecting their fate with engineering, robotics, automation or information technology. It will be of interest to those who like to solve complex problems, are looking for new challenges and want to prepare for participation in high-level Olympiads. Also, thanks to the accessible style of presentation and rich illustrative material, it will be useful to teachers and mentors looking for modern teaching materials for the preparation of their students. The authors, united in a team, are well aware of the specifics of school training and the requirements of modern Olympiad tasks . Their style is a combination of professionalism, clarity and motivation, which makes the book not only an educational tool, but also a source of inspiration for young engineers. Inspired by the best traditions of scientific popularization and pedagogy, the authors create an exciting journey into the world of engineering systems, where each page awakens interest in science and technology. This book is not just a collection of tasks, but a full-fledged guide that will help young talents to unleash their potential, understand complex engineering ideas and prepare for victories at the Olympics. It deserves the attention of everyone who wants not only to learn, but to immerse themselves in the exciting world of engineering systems, understand its laws and learn how to apply knowledge in practice. In today's world, where technology plays an increasingly important role, "School Olympics SPbU 2021. Engineering Systems” is the key to the future, opening the door to the heights of engineering excellence and scientific achievement.