PLINK is a versatile program which supports data management, quality control, and common statistical computations on matrices of genomic variant calls, in a computationally efficient manner. In population genomics, it is frequently used to take care of the "basics," so they do not need to be reimplemented when a new type of analysis needs to be performed on such a matrix. I describe several of these basic operations, and discuss uses and pitfalls.
Keywords: Allele frequency; Hardy–Weinberg equilibrium; Linkage disequilibrium; Principal component analysis; Relationship inference; Sex inference; Variant call format.