The author of this book takes us on an interesting journey to explore the world of black holes, as it begins with our definition of these mysterious astronomical phenomena and explains the aspects of their composition and nature. It provides a detailed explanation of the concept of spacetime tissue and its relationship to black holes, and highlights the unique properties that distinguish each black hole, including mass and angular momentum. The author reviews what happens to the material when it falls into a black hole, focusing on the concept of "entropy", its characteristics and thermal dynamic processes. It is perfectly explained how to measure the weight of these mysterious phenomena. The book concludes by examining the reasons that call us to study black holes, reviewing its secondary effects that exceed the space surrounding it, and even extends its effect on the planet.