Holland Codes
The Holland Codes or the Holland Occupational Themes (RIASEC) are a taxonomy of interests based on a theory of careers and vocational choice that was initially developed by American psychologist John L. Holland.
The Holland Codes serve as a component of the interests assessment, the Strong Interest Inventory. In addition, the US Department of Labor's Employment and Training Administration has been using an updated and expanded version of the RIASEC model in the "Interests" section of its free online database O*NET (Occupational Information Network) since its inception during the late 1990s.