Fst is a measure used in population genetics to quantify the genetic differentiation between populations. It compares the genetic variation within populations to the genetic variation between populations. A higher Fst value indicates greater genetic divergence, suggesting that populations are more distinct from each other. Fst values range from 0 to 1. A value of 0 means that there is no genetic differentiation, indicating that populations are genetically similar. Conversely, a value of 1 signifies complete genetic separation, meaning that the populations do not share any genetic variation. This metric helps researchers understand evolutionary processes and population structure.