It is usually written by a technician, product developer, or a company's customer service staff.
On the cover of this device are passages of text which describe the features and operation of the mechanism.
This was a unique problem for software developers, since users often became frustrated with current help documents.
[2] Some considerations for writing a user guide that developed at this time include: Before Unix, for example, GCOS, mainframe documentation were printed pages, available on-premise to users (staff, students...), organized into steel binders, locked together in one monolithic steel reading rack, bolted to a table or counter, with pages organized for modular information updates, replacement, errata, and addenda.
The term guide is often applied to a document that addresses a specific aspect of a software product.