Abstract: The ASTRAL family of tools infer species trees from a collection of gene trees or alignment sites based on quartets. This family has now been implemented under the same package called ASTER. The methods included are ASTRAL-IV for inference from single-copy gene tree topologies; ASTRAL-Pro for inference from multi-copy gene tree topologies; wASTRAL for inference from single-copy gene trees with topology, branch length, and support; and CASTER for inference directly from alignment sites. All the methods employ similar optimization strategies, differing primarily in their optimization scores. In this tutorial, we will explore this family of tools, focusing on the input, output, and main features that are shared among or differentiate the four subtools. All the tools are available under https://github.com/chaoszhang/ASTER and a paper describing the package is available at https://doi.org/10.1093/molbev/msaf172