The article provides an overview of black holes, discussing their observational evidence, properties, and recent theoretical developments. Black holes are formed when sufficient mass is compressed into a small enough volume, leading to a region where nothing can escape, known as the event horizon. The authors review the historical development of black hole theory, from Oppenheimer and Snyder's classic paper to modern research. They highlight the observational signatures of black holes, such as compactness, high orbital speeds, and strong X-ray emissions. The article also discusses supermassive black holes in galactic nuclei and black holes in X-ray binaries, emphasizing the importance of accretion processes and the Eddington limit. Additionally, it explores the uniqueness of black hole solutions in general relativity and the cosmic censorship hypothesis, which suggests that singularities are always hidden behind event horizons. The article concludes by discussing the connection between black hole thermodynamics and quantum mechanics, particularly in the context of string theory, where the microstates of black holes are related to their entropy.The article provides an overview of black holes, discussing their observational evidence, properties, and recent theoretical developments. Black holes are formed when sufficient mass is compressed into a small enough volume, leading to a region where nothing can escape, known as the event horizon. The authors review the historical development of black hole theory, from Oppenheimer and Snyder's classic paper to modern research. They highlight the observational signatures of black holes, such as compactness, high orbital speeds, and strong X-ray emissions. The article also discusses supermassive black holes in galactic nuclei and black holes in X-ray binaries, emphasizing the importance of accretion processes and the Eddington limit. Additionally, it explores the uniqueness of black hole solutions in general relativity and the cosmic censorship hypothesis, which suggests that singularities are always hidden behind event horizons. The article concludes by discussing the connection between black hole thermodynamics and quantum mechanics, particularly in the context of string theory, where the microstates of black holes are related to their entropy.