Quantum Mechanics is a fundamental theory in physics that describes the physical properties of nature at the scale of atoms and subatomic particles. It introduces concepts such as wave-particle duality, where particles like electrons exhibit both wave-like and particle-like behavior, challenging our classical understanding of physics. This theory also incorporates principles like superposition and entanglement, which allow particles to exist in multiple states simultaneously and to be interconnected regardless of distance. These phenomena have profound implications for technology, leading to advancements in fields such as quantum computing and quantum cryptography.