The OOH is more simplified. It looks at large groups of careers with similar skills (Clusters) and describes them in considerable detail. It takes a historical look at employment in the USA and makes projections on FUTURE employment in the USA. It is a project of the Federal Bureau of Labor Statistics.
The DOT is large, bulky and complicated. It attempts to include all current jobs within a category. Categories are smaller than clusters. A cluster may contain many categories. The print published DOT also attempts to describe specific information for each job, but the on-line WWW version is just a listing. It does not do historical or future projections. It is constantly being up-dated and revised. It may be 3 to 5 years behind the current time. It is project of the United States Employment Service. Supporting links:Dictionary of Occupational Titles Index and the US Department of Labor Employment and Training Administration
