A VERY high level intro on the most common segmentation strategies that are used across many marketers as well as a audience testing framework for beginners. The audience testing sheet that is included as a bonus, is a great tool for anybody that manages a Data management platform or does any audience testing across various media channels. At the same time, if you find yourself being a bit overwhelmed with all of the 1st 2nd or 3rd party data targeting options from, I'd highly recommend using a service like ClearSegment to understand various data providers - it's data collection methodologies as well as their individual segments. https://clearsegment.com/