This book does not have a logical organization, presenting each of the components of Bootstrap, but rather a practical organization in which we see the main elements of Bootstrap as it becomes appropriate to present them. It is a quick guide in which it offers, based on small tips or notes, the operation of the main components of Bootstrap and the reader can have an entry point to learn more easily about this technology. To follow this book you need to have a computer with Windows, Linux or MacOS, have knowledge of how to develop style sheets in CSS, JavaScript and basic Node. This book is currently in development. Map This book has a total of 8 chapters, it is recommended that you read in the order in which they are arranged and as we explain the experiments carried out, go directly to practice, replicate, test and modify the codes that we show in this book. Chapter 1: In this chapter we will give some key concepts about the frameworks, advantages of using Bootstrap and what changes it brings with its predecessor, in addition, we will prepare the development environment. Chapter 2: In this chapter we present an introduction to containers in Bootstrap as a fundamental structure to organize our content correctly on a website and have it displayed correctly; additionally, we introduce other common features such as Bootstrap breakpoints present in other components. Chapter 3: In this chapter we will learn how to use Bootstrap's grid and column system. Chapter 4: In this chapter we will learn how to work with the main components in Bootstrap, which are the fundamental elements in this technology. Chapter 5: In this chapter we will learn how to use the help classes in Bootstrap, also known as utility classes with which we can establish colors, margins, among other formats, to the HTML content. Chapter 6: In this chapter we will learn how to generate our custom Bootstrap bundle using Sass. Chapter 7: In this chapter we will create some composite or custom components using Bootstrap components and its utility classes as a base. Chapter 8: In this chapter we will build a real website that is a kind of product sales website or online store with a very limited scope. We will also create a website in which we will make fetch queries to an API.