Flare

Certainly not a tool for occasional users but clearly with the professional full-time technical writer in mind. Very powerful and professional. The optional add-on product Feedback Server allows you to obtain live user feedback on your documentation. You can view and track reader activity. Readers can leave comments within the documentation and rate individual topics. Another supplemental products are X-Review, X-Contribute and X-Edit, which allow casual content contributors such as subject matter experts (SMEs) to seamlessly provide and review content using defined guidelines.

Advantages: efficient integrated editor; excellent single source publishing features; creates PDF without the need of an external text processor; flexible layout options for the PDF output; also can generate full-featured Microsoft Word and Adobe FrameMaker files; DITA import (inluding relation tables); multiple tables of contents; professional translation workflow; sophisticated search features can be implemented within browser-based help files; concept markers make it easy to add structured related-topic links

Disadvantages: high price; rather complex to set up and use

Price: approx. $999; Feedback Server: approx. $2499; X-Edit: approx. $249; X-Review: free

http://www.madcapsoftware.com

Help & Manual

Extremely efficient, very professional and easy to use tool with an excellent price-performance ratio. Particularly recommendable if several product versions need to be documented from one common source, and printed user manuals (PDF) must also be supplied with minimum effort. The software comes with an efficient and powerful screen capture and graphics tool.

Advantages: easy to configure and use; excellent support for single source publishing (user-defined builds, snippets, conditional text with IF THEN ELSE statements, variables); efficient and powerful integrated manual generator (PDF) without the need of using external text processing such as Microsoft Word (Adobe Acrobat is not required either); HTML templates; style sheets; Unicode; efficient support for XML-based translation processes; automatic syntax highlighter for source code citations; team authoring support; integration with version control systems

Disadvantages: layout for printed user manuals (PDF) can be customized easily with the supplied print manual designer, however some advanced features such as automatic hyphenation, margin annotations or multi-column layouts are missing

Price: approx. $349 (Standard Edition) and $499 (Professional Edition)

http://www.helpandmanual.com

RoboHelp

For a long time RoboHelp was the unchallenged market leader of help authoring tools. Today, some of its competitors are clearly more innovative, but RoboHelp still remains one of the major tools. RoboHelp Server lets you easily deploy and manage up-to-date online content and control and monitor the use of web-based help systems in real time.

Advantages: very large scope of functions; efficient and powerful integrated HTML-editor; full control over the HTML code; version control; multi-author support; close integration with Microsoft Word and Adobe FrameMaker allows you to create online help from exiting printed user manuals; currently the only tool that creates online help in Adobe AIR and in Flash format

Disadvantages: high price; not as efficient and easy to use as some of its competitors; inefficient translation workflow

Prices: approx. $999 as a standalone product; also available as part of the Technical Communication Suite; RoboHelp Server approx. $1999

http://www.adobe.com/products/robohelp/

HelpStudio

One of the few tools that priviides built-in support for translations. Projects can either be translated in HelpStudio right away, or be exported to XML, translated by an external translator with the help of a translation memory tool, and then imported back into HelpStudio. Another interesting feature is the possibility to create your own widgets, which simplifies creating and editing complex content such as drop down sections, expand-in-place images, note boxes, includes etc.

Advantages: excellent translation support; good single source publishing capabilities;  PDF Output may have a different structure than the HTML output; basic screen capture tool included; full CSS support; efficient, customizable user interface; excellent HTML based editor with full code control; widgets; task lists; optional Community Extensions allow you to add interactive community features to a help system, such as private notes, public comments or a ratings bar; optional control to provide dynamic (embedded) help in an application

Disadvantages: output for PDF manuals can only partially be customized

Price: approx. €360; Community Extensions approx. €1200

http://www.innovasys.com

Fast-Help (also sold under the name EasyHelp)

In terms of program structure and functionality, somewhat very similar to both Help & Manual and HelpStudio. FastHelp focuses on other aspects in the translation process compared to Help & Manual, which is especially interesting if translations are done in-house, or if the author himself or herself is maintaining several language versions in parallel. For single source publishing Fast-Help is clearly less powerful than Help & Manual, especially when it comes to generating printed manuals.

Advantages: easy and intuitive to use; international and corporate versions have the option of translating projects directly in Fast-Help (parallel view of two languages)

Disadvantages: no XML-export for external translation, only few options to customize the output

Price: approx. $299 (Standard version), $399 (International version), $499 (Corporate version)

http://www.fast-help.com

HelpSmith

Still a rather young product, but increasingly catching up.

Advantages: low price; full support of styles; rather flexible layout options; good export for browser-based help; complete UNICODE support; basic team authoring support

Disadvantages: no conditional text; no export for external translation; no direct PDF output (only generates basic RTF); no HTML code control

Price: approx. $120

http://www.helpsmith.com

Author-it

As a mix of conventional Help Authoring Tool and database supported content management system, Author-it has a certain special standing. Needs getting used to, but the consistent object oriented approach is highly efficient. Unfurls its strengths only beyond a certain minimum project size and if you want to engage in intensive single source publishing. The optional product Author-it Aspect is a web based application that dynamically delivers content to users based on individual user profiles.

Advantages: very efficient and professional single source publishing; several authors can work simultaneously on a project; efficient support for XML-based translation processes; flexible reusability of topics even across projects; excellent export to Microsoft Word; unique authoring memory feature; Author-it can also be used for publishing web pages, presentation and training documents

Disadvantages: quite complex to set up and use; optimal use requires experience in single source publishing; high price

Price: upon request

http://www.author-it.com

Doc-To-Help

Has the unique option that it can work with Microsoft Word as editor, any HTML editor, or its own, built-in XHTML-based editor. This can be particularly interesting when data from different sources are delivered. Includes a tool that allows developers to easily embed a dynamic help pane in the application's interface and authors to map associate topics with the interface elements.

Advantages: flexibility; thorough and uniform support for conditional texts, variables and text snippets; good possibilities for single source publishing; partly automated documentation of source code and program libraries, team authoring support

Disadvantages: high price; no direct output to PDF (requires Microsoft Word)

Price: approx. $750 (Doc-To-Help for Word) and $1000 (Doc-To-Help Enterprise)

http://www.componentone.com

XDK

Closely linked with Microsoft Word but rather complex to use. Very rich set of advanced features.

Advantages: very large scope of functions; unique DHTML-Features (e.g., tab panes within a topic and sortable tables); high performance output for browser-based help (for example, master/slave dynamic merging), extensive documentation

Disadvantages: only restricted possibilities for single source publishing; inherits the weaknesses of Microsoft Word

Price: approx. €499

http://www.vmtech.com

Help Producer

Merely adds a small toolbar to Microsoft Word. However, don't be fooled: Help Producer is surprisingly efficient and powerful, and can be integrated seamlessly into Word-based workflows.

Advantages: comparatively low price; extensive customization possibilities (templates, style sheets, themes), COM scripting object model allows you to control the output and to automate complex tasks; supports Unicode; good conversion even for graphics that have been created with the graphic-function in Word

Disadvantages: only the most important customizations can be done using the user-interface

Price: approx. $395

http://www.mgtek.com

OfficeHelp

This Microsoft Word based help authoring tool is available in German language only. It implements a very interesting tab-based information design which makes it possible to provide a flat and simple table of contents even for extensive documents. Many useful functions add to or optimize the functionality of Microsoft Word (such as marginalia, conditional text, problem-free handling of numbered lists, comfortable cross reference function).

Advantages: very practical; many useful functions to evade typical Microsoft Word problems; excellent documentation (in German)

Disadvantages: only available in German; web help is not compatible with all browsers

Price: approx. €299 (Standard Edition) and €599 (Professional Edition)

http://www.officehelp.de

WebWorks ePublisher

Unmatched in performance, but also in its price. This tool is available in three versions: one version for Microsoft Word, one for FrameMaker and one for DITA-XML. If you have several licenses, it is even possible to generate common online help from different source formats. Those already familiar with early versions of WebWorks Publisher will be astonished at how simple it has become to use.

Advantages: excellent scope of functions, and at the same time easy to use; professional output; high flexibility coupled with low customization effort; can even handle "messily" formatted documents; conditional text and variables for Microsoft Word

Disadvantages: high price

Price: upon request

http://www.quadralay.com

ReWorx

Converts Microsoft Word documents into HTML, compiled HTML help, and XML + XSLT. The tool combines efficient conversion with a simple, wizard-based user interface.

Advantages: low price; easy to use; efficient output for browser-based help (including master/slave dynamic merging); can automatically eliminate typical text fragments found in printed user manuals, such as "on page"

Disadvantages: limited flexibility; only rudimentary support for conditional texts

Price: approx. €149 (Standard Edition) and €199 (Professional Edition)

http://www.vmtech.com/reworx.htm

Mif2Go

Converts FrameMaker files into online Help, DITA, Microsoft Word, and HTML for the Web. Powerful but far from being as intuitive as WebWorks ePublisher. Interesting especially in cases where custom conversions are needed that are not provided by "out of the box" converters. Mif2Go also is an interesting alternative if you need to closely integrate a conversion into a specific production processes.

Advantages: very affordable price; great flexibility and integration capabilities

Disadvantages: complex installation and customization required; uses proprietary "Document Coding Language" (DCL) for the configuration

Price: approx. $295; free for unemployed tech writers, students, academics, consultants

http://www.omsys.com

Word-2-CHM Converter and Word-2-Web/HTML Converter

Convert Microsoft Word documents into CHM or browser-based help.

Advantages: low price; easy to use; supports HTML templates

Disadvantages: no support of conditional content; no advanced features such as context IDs, text replacement in cross-references, etc.

Price: approx. $199 (Standard) and $299 (Professional)

http://www.macrobject.com

WordToWeb

Easy-to-use converter from Microsoft Word to CHM and HTML. Interesting especially if you want to import Microsoft Word documents into a web site.

Advantages: low price; simple configuration via wizards; flexibility

Disadvantages: only elementary support for browser-based help (among other things, no advanced table of contents, no full text search)

Price: approx. $299

http://www.solutionsoft.com

Doc-O-Matic

Professional documentation tool, particularly for source code and developer documentation. Output can be customized to a high degree.

Advantages: very efficient for source code documentation; high degree of automation; good support for single source publishing; able to directly export PDF manuals in a professional layout

Disadvantages: rather complex to use; translations must be done within the tool

Price: approx. $300 up to $1000

http://www.doc-o-matic.com

Document! X

Automates the process of creating and maintaining documentation particularly for complex components or XSD schemas.

Advantages: high degree of automation and flexibility; optional Community Extensions allow you to add interactive community features to a help system such as private notes, public comments or a ratings bar

Disadvantages: rather complex to use

Price: approx. €360; Community Extensions approx. €1200

http://www.innovasys.com

West Wind HTML Help Builder

Developed "by developers, for developers" this tool shows its strengths when it comes to documentation of source code and program libraries. At the same time, it is also one of the few tools of this kind that also meets the needs not just of developers but also of technical writers.

Advantages: comparatively low price; excellent support for source code-documentation of all major programming languages; consistent segregation of contents and formatting; support for different information types and templates; full control over the generated HTML code; HTML templates; clean Microsoft Word export including paragraph and character styles; multiple user support

Disadvantages: does not support conditional text and variables; needs Microsoft Word if you want to use thesaurus and spell check

Price: approx. $299

http://www.west-wind.com

TeeGofer Help Author for .NET Components

A tool for simple auto-documentation of .NET assemblies. Supports Unicode double-byte character sets.

Price: approx. $159

http://www.steema.com

VSdocman, VBdocman

Code Commenter and Generator of Class Documentation for VB .NET and C# / for VB.

Price: approx. $229 / $79

http://www.helixoft.com

GenHelp

Help Authoring for Component Writers. Imports Delphi Object Pascal, C++, C# and C files.

Price: approx. €60 (standard) and €140 (Professional)

http://www.frasersoft.net

TwinText

Automatically generates HTML and HTML Help documentation directly from code comments. Supports a wide range of programming languages.

Price: approx. $169

http://www.ptlogica.com

AS2Doc

Automatic documentation generator for ActionScript based classes. Various output formats and customization options.

Price: approx. €79

http://www.as2doc.com

VisDoc

Can generate HTML-based documentation from ActionScript and Java class files. Exclusively runs on Mac OS.

Price: approx. $40

http://visiblearea.com/visdoc/

HTML Help COM Assistant

Automatically analyzes components and creates basic online documentation for enumerators, objects, properties, and methods.

Price: free

http://www.devcomponents.com

Microsoft Sandcastle

Produces MSDN style documentation by reflecting over source assemblies. Optionally integrates XML Documentation Comments.

Price: free

http://www.microsoft.com

ROBODoc

Creates source code documentation by extracting comments from source code written in C, C++, Fortran, Perl, shell scripts, Assembler, DCL, DB/C, Tcl/Tk, Forth, Lisp, COBOL, Occam, Basic, HTML, Clarion, and any other language that supports comments.

Price: free (Open Source)

http://www.xs4all.nl/~rfsber/Robo/robodoc.html

Javadoc

Generates API documentation in HTML format from doc comments in source code.

Price: free

http://java.sun.com/j2se/javadoc/

HeaderDoc

Generates HTML reference documentation from comments in headers and source code written in C, C++, Objective-C , Java, JavaScript, Pascal, PHP, Perl, MIG, and shell scripts. Written in Perl for easy portability.

Price: free (Open Source)

http://developer.apple.com/opensource/tools/headerdoc.html

Doxygen

Documentation system for C++, C, Java, Objective-C, Python, IDL, Fortran, VHDL, PHP, C#.

Price: free (Open Source)

http://www.stack.nl/~dimitri/doxygen/

DoxyS

Code documentation tool for C++/C. Based on Doxygen.

Price: free (Open Source)

http://www.doxys.dk

VBDoxygen

Visual Basic add-in that converts VB code into java like syntax for processing via doxygen.

Price: free (Open Source)

http://sourceforge.net/projects/vbdoxygen/

Natural Docs

Scans code for comments written accoring to a special "natural-language-like" syntax and builds HTML documentation from this.

Price: free (Open Source)

http://www.naturaldocs.org

For more source code documentation generators and a side by side comparison, see: http://en.wikipedia.org/wiki/Comparison_of_documentation_generators

QuickHelp

Help authoring tool that can both author and run application help on Mac OS X, Linux and Windows. The software consists of a builder for authoring the help system and royalty-free viewer executables to ship with the application. The help files displayed by the viewer are XML-based. Within a displayed help file, user-initiated actions can popup messages, launch applications, run COM methods, apple events, AppleScripts or paste text into the clipboard. The system can also generate PDF files including table of contents and index.

Price: approx. $295

http://www.excelsoftware.com

HelpLogic

Another alternative for those who have to supply Apple Help (and browser based help, HTML Help, PDF manual – including title page, TOC, page numbers) from one source. The tool runs on Mac OS. It does not support conditional text and has no built-in WYSIWYG editor. If you not want to edit HTML, you must use your own WYSIWYG editor such as Dreamweaver or equivalent.

Price: approx. €75

http://www.ebutterfly.com/helplogic/

Simple Help Editor

Produces help content for viewing in Apple Help Viewer, Windows' HTML Help viewer, or a Web browser.

Runs on Windows and Mac OS.

Price: approx. $85

http://www.pandaware.com

Mac Help Writer

Builds help files for Mac OS X applications.

Price: approx. $50

http://www.artistictechworks.com/machelpwriter.html

HelpBlocks

Cross platform help authoring tool. Generates Microsoft HTML Help and wxWidgets HTML Help files.

Price: approx. €50

http://www.helpblocks.com

Helen

Platform independent authoring tool to create JavaHelp.

Price: approx. €169

http://www.software7.biz

HelpConsole

Dynamic, web-based help authoring tool with full support of conditional content, context sensitive help, PDF output and concurrent authors.
Price: approx. $299 up to more than $1,499

http://www.extremeease.com

HelpServer

Web-based solution for help and documentation. Can be deployed as a content management system and as a help system. Supports a large number of formats, such as PDF, HTML and video. Supports structured authoring and team authoring.
Price: upon request

http://www.helpserver.eu

exxDoc

Online multi-user, multi-language, and multi-database documentation system.

Price: starting at approx. $1000

http://www.pintexx.com

A number of tools automatically create some basic documentation by capturing screens from the software, by recording keystrokes or mouse movements, or by analyzing an application's internal resource files. While this approach will mostly not yield the same quality as manually created documentation, it be an efficient alternative for projects with a limited budget, a quick interim solution, or a good supplement to a training course.

ScreenSteps Desktop

Allows you to take screen captures of a software and to easily create step-by-step instructions based on these images. Screen captures can be updated with minimum effort when the software changes. Creates documentation that is primarily task-based. Available for both Windows and Mac OS. Provides little options and is therefore very easy to use. Output can be flexibly customized based on the applied templates. Excellent price-performance ratio.

Price: approx. $80

http://www.bluemangolearning.com

HelpBurner

Creates short documents with a focus on screen captures. The approach is quite similar to ScreenSteps Desktop.

Price: approx. $79

http://www.helpburner.com

Dr. Explain (Cognitive Force):

Automatically captures screens from an application and adds callouts and interactive navigation. Creates documentation that is essentially a GUI reference.

Price: approx. $125 up to $165

http://www.drexplain.com

Help Generator

Scans your application (Visual Studio, VB6, Microsoft Access, Microsoft Excel) and automatically generates HTML files, screenshots and other elements. Links the help topics to the appropriate application forms. Includes a full-featured Help Editor and screenshot tool.

Price: approx. $199 up to $299

http://www.helpgenerator.com

Recorder Express and RESITE Performance Suite

Recorder Express records your actions and exports content to Microsoft Word or XML.
RESITE Performance Suite provides a centralized, seamless documentation, training and online help solution. Primarily creates task-based help.

Price: upon request

http://www.insiteobjects.com

Manualizer

Solution to create user manuals and training documents and to document business processes step by step, based on screen captures with short comments. Specially designed for SAP applications.

Price: upon request

http://www.manualizer.ch

The following tools do not come with an integrated WYSIWYG editor. They can be used to generate documentation from a set of existing files (HTML or XML in most cases):

FAR HTML

Well-known toolbox, especially designed for those who create HTML help with a standard HTML Editor. The collection also contains tools to test and decompile CHM files.

Price: approx. $72

http://www.helpware.net

fpHelp Builder

Creates CHM help files from FrontPage or SharePoint Designer projects.

Price: approx. $12

http://www.fphelpbuilder.com

Precision Helper

Can be used to compile full-featured CHM from a set of HTML files. Also can be used to create basic browser based help from the same set of files, and to merge them into one singe HTML file. This single HTML file can then be imported into a text processor to create a printed user manual from the same source. Clear, modern user interface, support for context sensitive help and index keywords, helpful project management features.

Price: free

http://www.be-precision.com

CHM Maker

You can easily add any HTML files created with any HTML editor and compile them into one structured CHM file, including table of contents, index and full text search. An advanced key phrase detection engine automatically collects keywords from phrases in bold, italic, underlined text, in headers and table headers, and within <meta>-tags. You can customize this engine at your own discretion. The downside is that there is no support for context sensitivity.

Price: approx. $49

http://www.abeetech.com

HTML Help Workshop

Microsoft's compiler and basic editing tool for the compiled Microsoft Help format (.chm).

Price: free

http://www.microsoft.com/downloads/ (search for "help workshop")

HelpSetMaker

Tool to create help files, especially for the JavaHelp system. Creates JavaHelp HelpSets, HTML web pages and LaTeX source code. For Windows, Linux, Mac OS.

Price: free (Open Source)

http://sourceforge.net/projects/helpsetmaker/

AurigaDoc

Java-xml-xsl-based documentation tool for writing xml documents and converting them to other open formats like HTML, DHTML, PDF, PostScript, FO, RTF, Java Help and HTML Help (.chm). For Windows and Linux.

Price: free (Open Source)

http://aurigadoc.sourceforge.net

When creating or editing HTML files manually, the following tools may be helpful:

Dreamweaver

Price: approx. €535

http://www.adobe.com

Microsoft Expression Web

Price: approx. $149

http://www.microsoft.com

NetObjects Fusion

Price: approx. €90

http://netobjects.com

Web Page Maker

Easy-to-use web page editor that allows you to create web pages without having to know HTML. No HTML code control but possibility to insert HTML code snippets.

Price: approx. $49

http://www.webpage-maker.com

WYSIWYG Web Builder

Powerful visual web page editor. No HTML code control but possibility to insert HTML code snippets.

Price: approx. $45

http://www.wysiwygwebbuilder.com

KompoZer

Complete WYSIWYG web authoring application with file management, HTML, tag, WYSIWYG and preview modes, and CSS editor.

Price: free (Open Source)

http://kompozer.net

Amaya

W3C's editor and browser. Integrates editing and browsing functions seamlessly into one single tool.

Price: free (Open Source)

http://www.w3.org/Amaya/Overview.html

Quanta Plus

IDE for HTML, XHTML, CSS, XML, PHP and any other XML-based languages and scripting languages. Part of KDE.

Price: free (Open Source)

http://quanta.kdewebdev.org

Firebug

Firefox plugin. Lets you edit and debug and monitor CSS, HTML, and JavaScript live in any web page.

Price: free (Open Source)

http://getfirebug.com

Notepad++

Advanced code editor. Many specialized plugins available.

Price: free (Open Source)

http://notepad-plus.sourceforge.net

UltraEdit

One of the most powerful editors for text, XML, HTML, PHP, Java, Javascript, Perl, and other programming languages. Can also be used for comparing files, for advanced find and replace operations, and much more.

Price: approx. $60

http://www.ultraedit.com

Vantage Linguistics

Several linguistic search and checking products such as the AnswerWorks SDK.

Prices: upon request

http://www.vantagesoftwaretechnologies.com

MSHC Migrate Utility

Converts older help projects over to MS Help 3.

Price: free

http://mshcmigrate.helpmvp.com

chm2web

Flexible CHM to HTML converter. Converts help files in CHM format (HTML help) into a full-featured, browser-based, platform-independent help system.

Price: approx. €70 (Standard) and €130 (Pro).

http://chm2web.aklabs.com

HelpTron Converters

CHM To PDF Converter: Makes a PDF (including table of contents) from a CHM file.
HTML To PDF Converter: does the same as CHM To PDF Converter for plain HTML files.

Price: approx. €180

http://www.theta-software.com

Dawningsoft Converters

Provide a number of basic converting tools for Microsoft Word > CHM, PDF > CHM and vice versa.

Price: approx. $25 up to $50

http://www.dawningsoft.com

CHM-2-Word Converter

Converts CHM files into Word documents. Keeps the format, including images and tables.

Price: approx. $99 (Standard) and $199 (Professional)

http://www.macrobject.com

ABC Amber CHM Converter

Batch decompiler for CHM files. Transforms CHM files to PDF, RTF, HTML, DOC, HLP, TXT, DBF, XML, CSV, XLS, MDB and others. It creates the contents with bookmarks (in PDF, RTF, DOC and HTML), extracts pictures, keeps hyperlinks and the structure of CHM file.

Price: approx. $20

http://www.thebeatlesforever.com/processtext/abcchm.html

CHM Editor

WYSIWYG editor to edit existing CHM files. Also supports machine translation of existing CHM files via numerous internet machine translation services.

Price: approx. €49

http://www.chmeditor.com

HTML Executable

Creates stand-alone desktop EXE applications from websites or any group of HTML pages and linked media files.

Price: approx. €77 (Professional Edition) and €125 (Commercial Edition)

http://www.htmlexe.com

Some specialized indexing tools

Most help authoring tools allow you to add index entries easily. If you are, however, creating HTML pages manually, or if you are working with a word processor such as Word or FrameMaker, the following indexing tools may be helpful.

http://www.html-indexer.com

http://www.indexres.com

http://www.sky-software.com

http://www.editorium.com/dexter.htm

http://www.emdex.ca

http://www.fsatools.com

http://www.levtechinc.com

http://www.macrex.com

The following tools are clearly not as powerful as the market leaders. On the other hand, prices are significantly lower and most of these tools less complex to use. Therefore, for a small documentation project these can be interesting alternatives.

HelpMaker

Supports Unicode; WYSIWYG Editor with live spell checker and thesaurus. A basic screen capture utility and image editor are also included. Some functions are still under construction (for some years now). No support of style sheets, no HTML source code control, no conditional text, only very basic single source publishing support.

Price: free

http://www.vizacc.com

QuHelp

Scans a folder for HTML files and builds a browser-based help system with JavaScript-based navigation tree and full text search.

Price: free (Open Source)

http://www.badsectoracula.com/projects/quhelp/

JHelpDev

Assists you in creating a JavaHelp set from existing HTML files with an intuitive graphical user interface that relieves you from the task of manually editing the necessary XML files.

Price: free (Open Source)

http://jhelpdev.sourceforge.net

HelpSetMaker

Uses its own markup language for editing the help texts. Creates HelpSets for the JavaHelp online help system, web page sets for display in a browser and LaTeX source to be passed through "pdflatex" for obtaining a PDF document.

Price: free (Open Source)

http://www.cantamen.de/helpsetmaker.php?lang=en

HelpNDoc

Efficient tool for anyone who wants to generate a small CHM file with minimum effort at minimum cost. The generated output looks fine, but do not expect anything fancy. No support of predefined styles, no HTML editing, but the software even exports code snippets (C++, Delphi, Visual Basic) to call onlione help and supports variables within the text.
Price: free for nonprofit and non-commercial use; professional license approx. $59 (Standard) and $119 (Professional)

http://www.helpndoc.com

HelpTron HTML Help

Full-featured HTML Help authoring tool with basic PDF and Microsoft Word export. Full HTML code control, no conditional text, no text variables.
Price: approx. €179

http://www.theta-software.com

Helptrix

XML based; supports conditional output on element level; translation tool allows you to translate documents; very limited number of formatting-options / elements.

Price: approx. €39

http://www.helptrix.com

HelpCruiser

Supports styles, Unicode, basic PDF generation. No conditional text, no variables, no snippets.

Price: approx. €99

http://www.helpcruiser.com

Helpinator

Basic help authoring tool with HTML and RTF export options. Templates can de edited to customize the output. No conditional text. No support of predefined character and paragraph styles.

Price: approx. $99; free version for help files with up to 10 topics

http://www.helpinator.com

helpMATC Pro HTML

A very straightforward program with full HTML code control and CSS support. No single source publishing.
Price: approx. $69

http://www.helpmatic.net

Rolehelp

The key strength of Rolehelp is its outstanding simplicity. The downside is little flexibility. Can even generate basic printed PDF manuals (basic layout, cannot be modified). No support of predefined styles, no conditional text, no HTML code control, no index and full text search for browser-based help.

Price: approx. $59

http://www.roledata.com

WinCHM

Basic, easy to use help editor with full HTML code control, template support for HTML page design and basic PDF export. Can be executed from the command line. No advanced features such as conditional text.
Price: approx. $100

http://www.softany.com

Even if there may be more mature tools on the market today, the following programs show promising potential for the future:

ActoStudio

Integrated development environment for creating user manuals, software demos and presentations.

Price: approx. $499

http://www.softarex.com

nqDoc

XML-based, structured WYSIWYM (What You See Is What You Mean) documentation tool.

Price: approx. €60

http://www.nqdoc.com

digipedia

Aims to speed up the writing process by providing predefined topic types (XML based but no DITA) and standard single sourcing capabilities. The predefined structure cannot be changed. Multi user support, screen capture utility and image editor are included.

Price: approx. €810

http://www.digipedia.nl/en/