What is a technical communicator? In a phrase, an expert writer who talks about software, with software.
The technical communicator's concern is the endpoint, the moment of interaction between the user and the system. It's what some might call "the moment of truth" in software development because in the end, if the software fails there—no matter what the reason, the sophistication of the algorithm, the cadence of the process, the oversight unseen by the end user—it has failed totally.
Precision. Clarity. Insight. Correctness.
These aren't words; they're an immutable code programmed into the writer.
The Microsoft Manual of Style
The authoritative document of technical style. Everyone should have a copy.
The Chicago Manual of Style
For questions not answered by the MSTP, Chicago provides more guidance on usage and convention.
Technical Editing (Eaton and Rude)
For revising documents, there's no better guide for the information architecture, if you will, of documentation.
Primarily documentation: manuals and user guides. Additionally, UI text, troubleshooting documents, and occaisionally one-to-one support.
Entry-level Roles and Positions
Technical Writer I positions are so-named and easy to find. It's a matter of which industry you want to work in more than anything else.
The West Coast of the U.S. has two main influences: Start-ups, and the giants of Amazon and Microsoft.
The East Coast is a little different in my perception. There are still sizable technology companies, such as Red Hat, but you'll also find a huge concentration of the Defence Industry.
State of the Industry
Anecdotally, the prospects are strongest for hybrid programmer/writer.
Employment of technical writers is projected to grow 10 percent from 2014 to 2024, faster than the average for all occupations. Employment growth will be driven by the continuing expansion of scientific and technical products and by growth in Web-based product support. Job opportunities, especially for applicants with technical skills, are expected to be good.
—Bureau of Labor Statistics Occupational Outlook Handbook
Technical communicators are skilled at relaying the benefits of a project, and have some grip on the technical features as well.
As such, they have the ability to communicate with developers and executives, and because of their access to both audiences, the potential to go beyond a single role or type of role is great.
Some technical writers hail from the College of Fine Arts, others from Engineering.
For the former, it's important to bone-up on the technical: the tech comm should have at least some experience in hands-on development, even if they stay primarily focused on writing.
For the latter, it's important to understand that English (or other language of publication) is just as sophisticated a code for the representation of information.