Succinct tree sequences are an efficient way of representing the genetic history - often technically referred to as an Ancestral Recombination Graph or ARG - of a set of DNA sequences.

The tree sequence format is output by a number of external software libraries and programs (such as msprime, SLiM, fwdpp, and tsinfer) that either simulate or infer the evolutionary ancestry of genetic sequences. This library provides the underlying functionality that such software uses to load, examine, and manipulate ARGs in tree sequence format, including efficientaccess to the correlated sequence of trees along a genome and general methods to calculate genetic statistics.