Employee vs. independent contractor
Generally, a worker who performs services for an employer is considered to be an employee if the employer controls what the worker will do and how the work will be done. The key factor is that the employer has the right to control the details of how the services are performed, even if the employee has substantial freedom of action.
In contrast, an independent contractor performs services required by an employer but is not subject to the employer's control of how the services are performed.
If you need help determining the status of an employee, see: