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Black holes are regions in space with such strong gravity that nothing, including light, can escape. They were first described by Albert Einstein's theory of general relativity, which explains how massive objects warp space and time. Inside a black hole is a point of infinite density called a singularity surrounded by an event horizon, beyond which nothing can return. Black holes come in various sizes and masses, with the largest found at the centers of galaxies. Although they cannot be directly observed due to their light-trapping nature, scientists have inferred their presence through gravitational effects on surrounding matter and light. Researching black holes has provided valuable insights into space, time, and fundamental physics, and recent advancements have led to the capture of the first direct image of a black hole using the Event Horizon Telescope. Overall, black holes are fascinating cosmic phenomena that continue to captivate scientists and the public alike.