  Terrestrial laser interferometers for gravitational-wave detection made the
landmark first detection of gravitational waves in 2015. We provide an overview
of the history of how these laser interferometers prevailed as the most
promising technology in the search for gravitational waves. We describe their
working principles and their limitations, and provide examples of some of the
most important technologies that enabled their construction. We introduce each
of the four large-scale laser interferometer gravitational-wave detectors in
operation around the world today and provide a brief outlook for the future of
ground-based detectors.
