A self-employed person is an individual who works for himself/herself, as opposed to working for a separate entity such as another company. One can be considered self-employed if he or she is a freelancer, an independent contractor, or a business owner who has sole ownership of the business. Today, there are many fields wherein one can become self-employed, and the number of self-employed individuals continue to rise.
Most of the time, self-employed persons work in a field that makes use of the human creative faculties. This is perhaps largely due to the nature of the work. Some popular fields where freelancers reign supreme include writing - all the different kinds: technical, proposal, content, etc., web design, web development, graphic design, and social media. In fact, these jobs are very much in demand these days, and self-employed individuals are often the first choice of entities looking for someone to do some work for them.
Some would contest that owning a business is not the same as being self-employed. However, someone who runs a small business on a daily basis - with a hands on approach - can be considered self-employed. This is particularly true for individuals who may open a small shop and man the shop themselves.
There are many advantages to being self-employed, not the least of which is being in control of your own time. Applicable taxation schemes are also different as compared to those who are employed by another entity. Tax laws for self-employed people differ depending on the state and country, so it is best to check with an accountant for these matters.