What does a technical writer do? They engage in precision writing that explains a product or process. If you have ever actually read the instruction manual for a gadget, computer, etc. that is an example of technical writing. It requires great attention to detail, organization and skill.
A technical writer not only needs strong writing and organization skills, they also need to have knowledge in the subject they are writing about. If you don't know everything there is to know about a computer besides press the on button - you won't cut it as a technical writer ;). However, if you can teach someone who knows nothing more than how to push the button exactly how to work their new gadget in clear, concise, easy to understand language - technical writing may be the field for you.
A technical writer who is writing a manual for a product will spend a great deal of time researching the product. In addition, the writer will also spend time exploring the object to understand thoroughly how it works and how to explain the process to others. After this, the writer will prepare a document of step-by-step instructions, often including a diagram of working parts, a full "how to" guide and for many modern products an additional "quick start" guide for the impatient with short attention spans among us.
This is what is involved for simpler techincal writers. For more advanced technical writers, those who write manuals for highly specialized medical equipment for example, the process is much more complex, often involving teams of writers. For these projects, you would need to have very advanced knowledge and skills dealing not only with technical writing, but the highly specialized equipment itself. Those with engineering degrees tend to do well in technical writing fields also.
According to SimplyHired - the average salary of a technical writer is a respectable $52,000 per year nationwide.