Typically testing “Typical” in a typical manner, app note here (PDF!) from Maxim:
Typical (typ) is typically the most misunderstood word in Integrated Circuit (IC) testing. Typical values can’t be tested directly because they are a statistical value. We discuss how to read a data sheet to understand what parameters are tested and under what conditions. Fabrication (fab) parameters are highlighted including process standard deviation, fab process corners, six sigma quality guard bands, and defective parts per million opportunities (DPMO) concepts.