Since its launch in 2008, NASA’s Fermi Gamma-Ray Space Mission has made major discoveries on the nature of the high-energy sky. Fermi’s Large Area Telescope (LAT) one of the instruments on the satellite surveys the entire sky every 3 hours. It has discovered more than 4,000 new sources of gamma-rays. These include detections of hundreds of active galaxies, providing fresh insight into how supermassive black holes can accelerate jets of particles moving close to the speed of light. Fermi has found scores of new gamma-ray–emitting pulsars, a huge leap on the six known before launch. Most remarkably, a significant fraction of these pulsars are shining only in gamma-rays and are undetectable at other wavebands. In 2010, Fermi made the American Physical Society’s top 10 physics-related news: the stunning discovery of two gigantic bubbles of gamma-ray emission emerging from the Milky Way Galaxy. The gamma-ray burst monitor, a second instrument on this satellite, is finding bursts of gamma-rays on all cosmic distance scales and was fundamental to discovering the counterparts to the gravitational wave signal of merging two neutron stars. In this talk, I will discuss the implications of these observations and report on the latest exciting new results.