This it not the TYPE of job, but by INDUSTRY it appears from looking at the LED (Longitudinal Employer-Household Dynamics) description.

The difference is incredibly important. Have 500 workers including janitorial, secretarial, programmers, and executives at a high-tech company and they are all reported as high-tech workers regardless if the highest tech they touch is a floor waxer. Or have some IT people at a hotel and they are classified as hospitality.

I never like these industry classifications because they aren't actually very helpful in looking at employent statistics except in aggregate.