The Code of Practice for Determining Employment or Self-employment Status of Individuals (pdf) contains criteria which can be used to clarify whether a person is employed or self-employed. In most cases, it is clear whether a person is an employee or not.
The 708 area code belongs to the state of Illinois (IL) and some of the locations covered are Cicero, Oak Park and more:
Then in 1996 portions of area code 708 were split to form area codes 847 and 630. Area code 464, which is not yet in service, has been proposed as an overlay of area code 708. Counties in Illinois within area code 708 include: Cook County, DuPage County and Will County.