This book is designed for both advanced students in career mathematics courses and beginning graduate students. The topics covered in this book are a classic approach to the main ideas of general topology, but here the reader is also encouraged to learn about current research problems. The authors endeavored for each topic to contain a large number of illustrations, examples and problems that complement the theory and arouse the interest of the reader in order to deepen the study of this branch of mathematics. Each chapter contains a section called “chapter notes,” where evidence of claims made in the chapter is presented, alternative demonstrations, information supplied is complemented with curiosities or current data, or related topics are introduced that are not found in classic books. topology.