Every human grows from a single-celled embryo that contains an entire genome of determinants for what this embryo will become. For each one of us, this single cell became two, then four, and its genome became the genome of every cell in our body. However, over a lifetime of cell divisions and routine functioning, mutations in individual cells accumulate. The cells in our body, the highly infectious viruses, the bacteria in our gut, and the cells of a deadly tumor, have variable discrepancies between their genomes. Current biology excels at finding a given mutation in a host of cells that may beget a genetic disorder or lactase persistence, but we still lack the ability to find discrepancies between individual cells within a larger population. However, new technologies with single cell precision have the potential to transform research ranging from microbiology to disease genetics. The ability to extract an entire genome from a single cell could revolutionize our ability to differentiate genotypes within a population of cells and pinpoint cells that have spontaneous mutations in their genome that separate them from the others around them. Without single cell sequencing, genetic variation among single cells is generally intractable because sequencing techniques require many cells to provide enough input to create a readout. Single cell sequencing has the potential to enhance the study of topics ranging from cancerous tumor development to neuronal differentiation in the brain. With this broad set of motivations, scientists in the last decade have undertaken the task of finding a method to accurately and reliably sequence the genomes of single cells as the next step in the sequencing revolution.