Entanglement is a phenomenon in quantum physics where two or more particles become connected in such a way that the state of one particle is dependent on the state of the other, regardless of the distance between them. This property was famously described by Albert Einstein as "spooky action at a distance," and has since been extensively studied and utilized in various fields such as quantum computing, cryptography, and teleportation. Entanglement is a fundamental aspect of quantum mechanics and plays a crucial role in understanding the nature of the universe at a fundamental level.