Gravitational waves were first directly detected by the LIGO detectors in US on 14th September 2015. A century ago - in 1916 - Einstein predicted the existence of gravitational waves. Pioneering efforts by Joe Weber began in the 1960s for detecting these waves using resonant mass detectors. The existence of the waves was established by the observations of the Hulse-Taylor binary pulsar whose orbit decays exactly as predicted by Einstein's general theory of relativity - Nobel prize in 1993. Weakness of the gravitational force implies that the waves are extremely difficult to detect - one must effectively measure distances much smaller than the size of a proton. During the past half century, technology has taken immense strides and the current advanced detectors are now capable of reaching the requisite sensitivity to detect the waves. Gravitational waves carry information about their dramatic origins and about the nature of gravity that cannot be otherwise obtained. A new astronomical window to the universe has been opened. This talk will describe the physics of gravitational waves, the unprecedented requirements from technology and the detector, the current & future global efforts in this direction, the description of the gravitational wave events that were detected, the Indian contribution to the global effort and the astrophysics that we can learn from this.