User Manual
A user guide, also commonly known as a manual, is a technical communication document intended to give assistance to people using a particular system. It is written by a technical writer.
User guides are most commonly associated with electronic goods, computer hardware and software.
Most user guides contain both a written guide and the associated images. In the case of computer applications it is usual to include screenshots of how the program should look, and hardware manuals often include clear, simplified diagrams. The language is written to match up with the intended audience with jargon kept to a minimum or explained thoroughly.