Stephen Hawking's theories revolutionized cosmology, especially his work on black holes and the nature of time. His development of the Hawking radiation concept challenged existing notions about the unbreakable nature of black holes, suggesting that they could emit radiation and eventually evaporate. This fundamentally altered scientific perceptions of these cosmic phenomena. His book, A Brief History of Time, made complex ideas accessible to the public, sparking widespread interest in physics. Hawking's contributions extend beyond theoretical insights as they have inspired advancements in various fields, fostering a greater understanding of the universe and our place within it.