The development of DNA sequencing technologies in the late 70s has provided scientists with the ability to decode the DNA sequence first of just individual genes, then of entire organisms. In recent years technological advances have resulted in dramatic reductions in the cost of sequencing, coupled with a substantial increase in the throughput of a single instrument. These advances have made it possible for scientists to shift their focus from the analysis of single organisms to entire populations. In my talk I will outline several research areas made possible by the new "sequencing revolution" and will describe associated computational challenges. In particular I will focus on recent research in my lab on algorithms for analyzing new generation sequencing data, and on the analysis of microbial communities (metagenomics).