The IAB (Internet Advertising Bureau) maintains a list of categories and subcategories that can be targeted with Ad Servers or Demand Side Platforms. Sometimes referred to as the IAB Content Taxonomy, most people in the advertising industry refer to it as IAB Categories List. The IAB categories and subcategories are applied mostly on the publisher site in the website setup phase, thus allowing the Advertiser / Buyer the ability to target sites in that category.
The IAB Contextual Taxonomy was first developed in consultation with taxonomy experts from Academia, Ad Measurement companies, and members of the IAB Networks & Exchanges Committee then the IAB Tech Lab Taxonomy Working Group.
The IAB Categories List provides somewhat very basic targeting compared with details contextual targeting that Healthy Ads offers. For example, Healthy Ads offers 100+ contextual targeting options in Health & Fitness across areas like General Health, Medical Conditions, Chronic Diseases and Infections to name a few.
Review all of Healthy Ads Targeting Options here