Loop Quantum Cosmology (LQC) is a branch of quantum cosmology that applies principles of loop quantum gravity (LQG) to cosmological settings, focusing on the quantum geometry effects of LQG. These effects introduce a new repulsive force that becomes significant at the Planck scale, resolving classical gravitational singularities. In cosmological models, Einstein's equations are modified in the Planck regime, leading to the resolution of singularities and the resolution of conceptual issues such as the 'horizon problem.' LQC has seen significant recent activity, with contributions from quantum gravity experts, mathematical physicists, and cosmologists. The article provides an overview of LQC for three audiences: young researchers, the quantum gravity community, and cosmologists interested in applying LQC to probe modifications in the standard paradigm of the early universe. It covers the evolution of cosmological paradigms, the limitations of quantum cosmology, key questions in quantum cosmology, and the development of LQC. The article discusses the Hamiltonian framework for the k=0 FLRW model, the WDW theory, and the role of quantum geometry. It also explores the exactly soluble LQC (sLQC) model, generalizations to models with spatial curvature, effective dynamics, and phenomenological implications. The article further delves into beyond homogeneity models, such as Gowdy models and quantum field theory on cosmological quantum spaces, and the observational consequences of LQC. Finally, it discusses the lessons learned from LQC for full quantum gravity, including the Hamiltonian constraint, spin foams, and consistent histories.Loop Quantum Cosmology (LQC) is a branch of quantum cosmology that applies principles of loop quantum gravity (LQG) to cosmological settings, focusing on the quantum geometry effects of LQG. These effects introduce a new repulsive force that becomes significant at the Planck scale, resolving classical gravitational singularities. In cosmological models, Einstein's equations are modified in the Planck regime, leading to the resolution of singularities and the resolution of conceptual issues such as the 'horizon problem.' LQC has seen significant recent activity, with contributions from quantum gravity experts, mathematical physicists, and cosmologists. The article provides an overview of LQC for three audiences: young researchers, the quantum gravity community, and cosmologists interested in applying LQC to probe modifications in the standard paradigm of the early universe. It covers the evolution of cosmological paradigms, the limitations of quantum cosmology, key questions in quantum cosmology, and the development of LQC. The article discusses the Hamiltonian framework for the k=0 FLRW model, the WDW theory, and the role of quantum geometry. It also explores the exactly soluble LQC (sLQC) model, generalizations to models with spatial curvature, effective dynamics, and phenomenological implications. The article further delves into beyond homogeneity models, such as Gowdy models and quantum field theory on cosmological quantum spaces, and the observational consequences of LQC. Finally, it discusses the lessons learned from LQC for full quantum gravity, including the Hamiltonian constraint, spin foams, and consistent histories.