These terms simply reflect that traditional science, engineering, technology distinction we see in all fields. That is:

ScienceEngineeringTechnology
Biology (human) Medical Doctor Medical Technologist, X-Ray Technician, Nurse
Physics (electrical) Electrical Engineer Electrician
Phyics (materials, mechanical) Civil Engineer General Contractor, Construction Worker
Chemistry Chemical Engineer Factory worker at a chemical plant
Computer Science Software Engineer Information Technology worker, network admin, computer admin