Most large businesses tend to have good technical writers on their payroll, writers who understand the domain and have the ability to explain difficult concepts simply. However, small and medium businesses cannot afford that luxury, but have the same needs. Contracting this work out to writers is the best way for these companies to get the work done easily - and also offers writers with the right expertise substantial income opportunity. Each such project, depending on complexity and size, could fetch you $500 to $1000. Experience, expertise and networking are key ingredients for obtaining such work on an ongoing basis and have it develop into a source of extra income.
Copywriting is a completely separate domain that can prove very lucrative, but is also a hard task-master. If the copy you write for a company's product is chosen and mailed out, that can fetch you a handsome sum of money (north of $10,000 is not uncommon). If that copy performs superbly and becomes their new control, you are on your way to making big bucks (north of $100,000) and will now get a steady diet of new assignments. But often, on the downside, you will also be measured by "What have you done for me lately?". Mastering the art of repeatedly producing winners is the secret of a successful career as a copywriter.
Writing for websites and e-zines is the new domain that has opened up for writers, though most website owners continue to use in-house services for website writing. There is now a slow but growing realization that using powerful copy on the site has a direct effect on conversion rates, and it pays to have a good writer do that work. Also, the monotonous work of producing original fresh content for a site or its e-zine is also having more and more website owners looking to outsource that work to good writers. Keep an eye out for this growing opportunity, and seek to advertise your work in sites that look for bids on projects and ongoing work.
Other options such as ghostwriting books, producing translations of great works from one language into another, as well as maturing into a regular writer for magazines should be additionally explored as a pathway to a regular income as a writer - though each one requires expertise, name recognition, and careful marketing before it can become a source of regular income.

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