Discussion of gravity waves has been ongoing for many decades.  Gravity waves are similar in concept to electromagnetic waves, i.e. radio, light, X-rays, etc.  Gravity, however, is much weaker than electromagnetic forces.  Just as electric current moving back and forth in an antenna creates radio waves, objects moving around each other in orbits emit gravitational waves.  Because gravity is so much weaker than electromagnetic forces, it takes truly massive objects to make gravitational waves we can detect.  Everybody expected gravitational waves to exist, the challenge was to make a receiver sensitive enough to detect them.  Basically no practical importance as far as human existence is concerned.  However, the detection of the gravitational waves is a brilliant feat of experimental physics.