This document provides an overview of water harvesting techniques used historically and currently around the world. It discusses how water harvesting has been practiced for thousands of years in arid regions to irrigate crops and provide drinking water. The document then summarizes various water harvesting methods used historically in regions like the Middle East, Africa, Asia, and the Americas. It outlines factors to consider when implementing water harvesting systems, such as rainfall patterns, land use, topography, and maintenance requirements. The purpose is to provide context around water harvesting and define different techniques while examining its use and resurgence today.