Space X was the first to land a booster rocket on a floating platform in the ocean so it can be reused again. That achievement is a huge step forward in making space travel (slightly) less insanely expensive because now they can use that booster rocket multiple times. Prior to that the hundreds of millions of dollars in booster rockets either sank to the bottom of the ocean, or is still floating through space, waiting to burn up on re-entry into the atmosphere.

But now both Space X and Blue Origin have successfully landed their boosters on floating ocean platforms.

Check out this cool video, especially for space nerds like me.