Black hole physics studies the properties and behaviors of black holes, regions in space where gravity is so strong that nothing, not even light, can escape. They form when massive stars collapse under their own gravity at the end of their life cycles. The boundary surrounding a black hole is called the event horizon, beyond which no information can return. Inside a black hole, the laws of physics as we know them break down. The core, known as the singularity, is where matter is thought to be infinitely dense. Scientists use theories like general relativity to understand these phenomena, but many aspects of black hole physics remain mysterious.