X-ray emission traces signatures of energetic and violent events associated with formation and evolution of all structures in the universe. Studies of X-ray sky are relatively recent, as the first X-ray cosmic sources were detected only sixty years ago, while the optical sky has been known to humans since the beginning of life. Over the past two decades, our view of the X-ray universe has been significantly improved thanks to the NASA’s Chandra X-ray Observatory. Chandra, with its extremely sharp X-ray vision enabled by large-area, sub-arcsecond mirrors, has revolutionized our understanding of the high-energy sky. It has brought many important astrophysical processes into focus for the first time and has comprised a key component of our multiwavelength view of the Universe. In this talk I will give a broad overview of the science enabled with Chandra and focus on a handful of the exciting results, including breakthrough discoveries on the births and deaths of stars, the cosmic growth of black holes, and the formation and evolution of galaxies and clusters. I will conclude with a look toward the future of high-resolution X-ray observatories.