This document describes the WoW UI Customization aspect of load order for loading AddOns. It covers when the WoW client first starts up, when AddOns load for the first time, and when user or WoW reloads the UI. The availability of the Lua environment at various points in the process is also detailed. The term 'WoW Client' means: the WoW game program that's launched to play WoW.