A freelance writer essentially has his or her own business. Any work done for an outside organization or employer is done on a part-time or contract basis. From the business side of things, this means the business owner is responsible for expenses, taxes, local licenses, and any medical or insurance benefits a full-time employer might provide. If this sounds overwhelming, keep in mind that you also keep all the profits!
Freelance writing can have a number of different definitions. Understanding these differences can help you make an intelligent decision about where to take your writing.