A genome is an organism's complete set of DNA, including all of its genes. Each genome contains all of the information needed to build and maintain that organism. In humans, a copy of the entire genome—more than 3 billion DNA base pairs—is contained in all cells that have a nucleus. Genome typing is the simultaneous genotyping of tens to hundreds of marker loci from across the genome in a single or few experiments (for example, by PCR amplification). Population genomics has the potential to improve studies of evolutionary genetics, molecular ecology and conservation biology, by facilitating the identification of adaptive molecular variation and by improving the estimation of important parameters such as population size, migration rates and phylogenetic relationships. There has been much excitement in the recent literature about the identification of adaptive molecular variation using the population-genomic approach. However, the most useful contribution of the genomics model to population genetics will be improving inferences about population demography and evolutionary history. Statistical tests and software programs for detecting outlier loci and analysing population-genomic data are becoming increasingly available; nonetheless, the development and validation of tests and software is the greatest impediment to the advancement of population-genomic approaches. The population-genomics paradigm can facilitate biodiversity conservation through rapid biodiversity screening, identifying appropriate populations for translocations (to rescue declining populations) and focusing conservation efforts on preserving processes of evolution (adaptive change).