This article provides a comprehensive review of the magnetic behavior of pyrochlore oxides, specifically $A_{2}^{+}B_{2}^{+}O_{7}$ where $A$ is a rare-earth ion and $B$ is usually a transition metal. These materials form a network of corner-sharing tetrahedra, creating a geometrically frustrated magnet. The review covers the historical perspective, theoretical background, and experimental results on various aspects of these materials, including long-range ordered phases, spin glass phases, spin ice phases, and spin liquid phases. It also discusses the effects of external perturbations such as magnetic fields and high pressure. The article aims to provide a broad overview of the diverse phenomena observed in pyrochlore oxides, highlighting the unique properties that arise from geometric frustration.This article provides a comprehensive review of the magnetic behavior of pyrochlore oxides, specifically $A_{2}^{+}B_{2}^{+}O_{7}$ where $A$ is a rare-earth ion and $B$ is usually a transition metal. These materials form a network of corner-sharing tetrahedra, creating a geometrically frustrated magnet. The review covers the historical perspective, theoretical background, and experimental results on various aspects of these materials, including long-range ordered phases, spin glass phases, spin ice phases, and spin liquid phases. It also discusses the effects of external perturbations such as magnetic fields and high pressure. The article aims to provide a broad overview of the diverse phenomena observed in pyrochlore oxides, highlighting the unique properties that arise from geometric frustration.