Anyone who works for you, and is not genuinely self-employed, is either a worker or an employee.
Employees have a contract of service and are usually required to work a set or minimum number of hours per week.
A worker will also work under some form of contract (it doesn’t need to be written) but has fewer employment rights than an employee, such as protection against unfair dismissal or time off for emergencies. They will usually have fewer obligations to their employer, for example, casual workers or agency staff can usually decline work offered to them.
Self-employees are responsible for their own business. They are not paid through PAYE, and they do not have the same rights and responsibilities of an employee or worker.
An organisation can regard someone as self-employed for tax purposes. However, employment rights and health and safety duties may still fall to the employer depending on the nature of the contract and the way work is being carried out. An employment tribunal can make a decision over their employment status.