Independent contractor
A worker who is in business for themselves and paid without tax withheld, often reported on a Form 1099-NEC. They pay their own self-employment tax.
An independent contractor controls how the work gets done, often uses their own tools and can work for several clients. The business that pays them does not withhold income tax or pay half of Social Security and Medicare.
The IRS decides employee or contractor status by looking at behavioral control, financial control and the relationship, not by the job title. Either side can ask the IRS to decide with Form SS-8.
Example
A designer paid $60,000 as a contractor owes about $8,478 in self-employment tax, versus $4,590 withheld from the same pay as an employee.