Public Libraries is a unique technology available to the Abbasid Dynasty in Age of Empires IV introduced in patch 11.1.1201. It can be researched at the House of Wisdom (with the Culture Wing upgrade) in the Imperial Age. It increases the hit points of Villagers and Traders by +2 for each economic technology researched. This technology stacks with Textiles, so if the latter is researched, Villagers gain +3 for each technology. The maximum possible number of hit points is 141 for Villagers, and 160 for Traders.
While in Golden Age Tier 2/3, the research speed of this technology is +15%/+20%, respectively. If Preservation of Knowledge has been researched, this technology costs -20%.
