Excerpt
Before I begin, according to WordWeb®, a program I use often:

Freelance used as a Verb:

Work independently and on temporary contracts rather than for a long-term employer

Freelance used as an Adjective:

Working for yourself

Freelance used as a Noun:

A writer or artist who sells services to different employers without a long-term contract with any of them

What does this mean in plain English?

It means, as a freelancer, it is up to you to keep impeccable records of income and expenses (record keeping for taxes), medical and dental insurance, marketing, Web design, anything related to business is up to you. Freelancers receive no befits from employers, because freelancers are considered independent contractors.