Technical writing is a process of producing technical / semi-technical / even (sometimes) non technical content for IT or non IT field related software, process, or product in a clear, concise, and transparent way. The technical writing includes (but not limited to) the following checkpoints:
Education: Basically a technical degree or a degree in English language or journalism is preferred for technical writing.
Information gathering: The information can be gathered by interviewing clients, SMEs, project team members like developers, testers etc., or through documents from the project/organisation repository.
Language (authoring and proofreading): The language used in the document shall be grammatically correct, error free and simple. There are many writing standards and styles that can be used to keep the language consistent and improve the quality of the documents. Active voice and present tense shall be used to frame sentences. Main point to remember is to “Write the content to inform but not to impress.”
Formatting: All the content produced shall be well formatted and consistent throughout the document(s). Again there are many formatting standards to follow, the knowledge of such standards is essential in technical writing.
Tools expertise: Knowledge (for freshers) and experience in authoring tools is mandatory for doing any technical writing projects.
Illustration and screen capturing tools: Even though graphic designers and illustrators will be handling these tasks. However, working knowledge of such tools is a must for technical writers for owning (lesser and smaller) illustrations and all the screenshots in their documents.
Publishing: The documents can be published through various mediums including physical copies, application formats (.doc, PDF etc.), online help or webpages.
Knowledge of SDLC, DDLC, Aerospace domain, mechanical industry and domain specific documentation standards is required for technical writing. There are many more areas to uncover but they will not be relevant to this quickly created, unformatted, non-peer reviewed write up as an introduction to technical writing.