A technician is a worker in a field of technology who is proficient in the relevant skills and techniques, with a relatively practical understanding of the theoretical principles. Experienced technicians in a specific tool domain typically have intermediate understanding of theory and expert proficiency in technique. As such, technicians are generally much better versed in technique compared to average layman and even general professionals in that field of technology. For example, although audio technicians are not as learned in acoustics as acoustical engineers, they are more proficient in operating sound equipment, and they will likely know more about acoustics than other studio personnel such as performers.
Technicians may be classified as either skilled workers or semi-skilled workers, and may be part of a larger (production) process. They may be found working in a variety of fields, and they usually have a job title with the designation 'technician' following the particular category of work. Thus a 'stage technician' is a worker who provides technical support for putting on a play, while a 'medical technician' is an employee who provides technical support in the medical industry or to the medical profession.