The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a joint project between Caltech and MIT, supported by the National Science Foundation. LIGO operates three multi-kilometer interferometers at two widely separated sites in the United States: Hanford, Washington, and Livingston, Louisiana. These detectors are designed to detect and study gravitational waves of astrophysical origin, which could provide insights into strong-field gravity and exotic objects like black holes and neutron stars. LIGO's sensitivity is unprecedented, capable of detecting gravitational wave strains smaller than one part in $10^{21}$. The data from these detectors are being analyzed to detect or place limits on gravitational waves from various potential sources. The article provides an overview of LIGO's detectors, their operation, and how they achieve their sensitivity, as well as a review of how their data can be used to learn about astrophysical phenomena.The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a joint project between Caltech and MIT, supported by the National Science Foundation. LIGO operates three multi-kilometer interferometers at two widely separated sites in the United States: Hanford, Washington, and Livingston, Louisiana. These detectors are designed to detect and study gravitational waves of astrophysical origin, which could provide insights into strong-field gravity and exotic objects like black holes and neutron stars. LIGO's sensitivity is unprecedented, capable of detecting gravitational wave strains smaller than one part in $10^{21}$. The data from these detectors are being analyzed to detect or place limits on gravitational waves from various potential sources. The article provides an overview of LIGO's detectors, their operation, and how they achieve their sensitivity, as well as a review of how their data can be used to learn about astrophysical phenomena.