Loop Quantum Cosmology (LQC) is a framework derived from Loop Quantum Gravity (LQG) applied to cosmological models. It introduces quantum geometry effects that create a repulsive force at the Planck scale, resolving singularities in general relativity. In LQC, quantum geometry corrections modify Einstein's equations, leading to a bounce instead of a singularity. The theory addresses key cosmological questions, such as the resolution of the big-bang singularity and the nature of quantum gravity. LQC has been developed through three stages, with the latest stage involving the $\bar{\mu}$ scheme, which resolves singularities without assuming periodicity in the extrinsic curvature. This framework has been extended to include spatial curvature, cosmological constants, anisotropies, and inflationary potentials. LQC also provides insights into effective dynamics, quantum corrections to inflation, and the behavior of gravitational waves near the bounce. The theory has been applied to various models, including Bianchi models and Gowdy models, and has shown promise in addressing conceptual issues in quantum gravity. LQC has also influenced the development of spin foams and group field theory, and has provided a basis for understanding entropy bounds and consistent histories in quantum gravity. The theory is currently being explored for its potential to explain observational phenomena and to constrain quantum gravity theories through cosmological observations.Loop Quantum Cosmology (LQC) is a framework derived from Loop Quantum Gravity (LQG) applied to cosmological models. It introduces quantum geometry effects that create a repulsive force at the Planck scale, resolving singularities in general relativity. In LQC, quantum geometry corrections modify Einstein's equations, leading to a bounce instead of a singularity. The theory addresses key cosmological questions, such as the resolution of the big-bang singularity and the nature of quantum gravity. LQC has been developed through three stages, with the latest stage involving the $\bar{\mu}$ scheme, which resolves singularities without assuming periodicity in the extrinsic curvature. This framework has been extended to include spatial curvature, cosmological constants, anisotropies, and inflationary potentials. LQC also provides insights into effective dynamics, quantum corrections to inflation, and the behavior of gravitational waves near the bounce. The theory has been applied to various models, including Bianchi models and Gowdy models, and has shown promise in addressing conceptual issues in quantum gravity. LQC has also influenced the development of spin foams and group field theory, and has provided a basis for understanding entropy bounds and consistent histories in quantum gravity. The theory is currently being explored for its potential to explain observational phenomena and to constrain quantum gravity theories through cosmological observations.