This guide explains the basics of computing in an accessible manner. Discusses the principles of electronic computing and the use of binary numbers; outlines how computer hardware functions, what an operating system does, and how data is transferred over the Internet. The reader will gain a basic understanding of programming languages by studying code examples in C and Python. Each chapter contains exercises and practical tasks (projects), allowing you to apply the acquired knowledge in practice. The book will be useful to anyone who wants to understand how a computer works.