A user guide or user's guide, also commonly known as a manual, is a technical communication document intended to give assistance to people using a particular system. It is usually written by a technical writer, although user guides are written by programmers, product or project managers, or other technical staff, particularly in smaller companies.
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 the human-machine interface(s), and hardware manuals often include clear, simplified diagrams. The language used is matched to the intended audience, with jargon kept to a minimum or explained thoroughly.
Contents of a user manual 
The sections of a user manual often include:
- A cover page
- A title page and copyright page
- A preface, containing details of related documents and information on how to navigate the user guide
- A contents page
- A guide on how to use at least the main functions of the system
- A troubleshooting section detailing possible errors or problems that may occur, along with how to fix them
- A FAQ (Frequently Asked Questions)
- Where to find further help, and contact details
- A glossary and, for larger documents, an index
Computer software manuals and guides 
User manuals and user guides for most non-trivial software applications are book-like documents with contents similar to the above list. The Starta User Manual is a good example of this type of document. Some documents have a more fluid structure with many internal links. The Google Earth User Guide is an example of this format. The term guide is often applied to a document that addresses a specific aspect of a software product. Some usages are Installation Guide, Getting Started Guide, and various How to guides. An example is the Picasa Getting Started Guide.
In some business software applications, where groups of users have access to only a sub-set of the application's full functionality, a user guide may be prepared for each group. An example of this approach is the Autodesk Topobase 2010 Help document, which contains separate Administrator Guides, User Guides, and a Developer's Guide. These guides are a valuable tool for On-the-job training.
- "Online Technical Writing: User Guides". firstname.lastname@example.org. Retrieved 13 August 2009.
- Gary Blake and Robert W. Bly, The Elements of Technical Writing, pg. 143. New York: Macmillan Publishers, 1993. ISBN 0020130856
- "Starta User Manual". Starta Development, Inc. 16 October 2006. Retrieved 13 August 2009.
- "Google Earth User Guide". Google. 4 June 2009. Retrieved 13 August 2009.
- "Getting Started with Picasa: Getting Started Guide". Google. 15 June 2009. Retrieved 13 August 2009.
- "Autodesk Topobase 2010 Help". Autodesk. Retrieved 13 August 2009.