Outliner

View of very basic outline with graphics. Notepad view in Ecco Pro.

An outliner is a computer program that allows text to be organized into discrete sections that are related in a tree structure or hierarchy. Text may be collapsed into a node, or expanded and edited.

Outliners are typically used for computer programming, collecting or organizing ideas, as personal information management or for project management. Mind Mappers and Wikis are related types of software.

Design

The principal attribute of outline editors is that they support or enforce the use of a hierarchy. For example:

• Editing: Sound parent-child relationships are enforced when the user modifies the document structure. For example:
  • Promoting, demoting, copying, or deleting a parent has the same effect on the children.
  • Every item entry must be within one level of its predecessor, such that each item must be a sibling or child of the preceding item (thus, no item can be a grandchild of the preceding item).
• Viewing: The tool enables the user to affect the display by level. For example:
  • Applying styles by outline level (e.g., bold all 1st level items)
  • Displaying selected levels (e.g., show all 1st and 2nd level items, but none deeper).
  • Hoisting an item hides all parent and sibling items; thereby focusing, or zooming in, on a particular branch. De-hoisting again reveals the full outline.
• Search: The tool retrieves all items that contain the query terms plus the ancestors (parent, grandparent...) that give them context.
• File import and export: Both the content and structure of outlines are conveyed when files are imported or exported (e.g., from and to tab-indented files).

Layout

Composing a Wikipedia article in OmniOutliner.

There are two basic types of outliners: one-pane or intrinsic, and two-pane or extrinsic, each with its strengths and weaknesses.

A one-pane outliner is known as an intrinsic outliner because the text itself is organized into an outline format—individual sections (such as paragraphs) of text can be collapsed or expanded, while keeping others in view. Everything is displayed within a single area, hence the term one pane. One of the strengths of one-pane outliners is that, because the text itself is what is structured and because several nodes of text are visible at once, it is easy to edit across sections. The drawback is that, because the structure is not always visible, there is not as strong an overview of the whole or ability to quickly navigate between sections as with a two-pane outliner. Some word processors, such as Microsoft Word, have an Outline Mode to help with structuring documents.^[1][2]

A two-pane outliner separates structure from content—the structure is extrinsic to the text. A tree structure with node titles is presented in one pane, and the text is shown in another. Since the structure is always clearly shown at all times separately from content, this format allows for a quick overview of the structure, and easy navigation. The drawback is that since only one node's worth of text is shown at one time and navigation has the additional step of crossing panes, the structure is more rigid, making editing across nodes more difficult. This view is similar to many file browsers and email programs (which can be thought of as three-pane outliners).^[3] This type of structure is useful also as a document management tool where the second pane is a document in place of textual information.

Ecco Pro with EccoMV pane.

A one- and two-pane outliner may be combined as a hybrid. This allows multiple notes' text and graphics to be shown at the same time. The organizational power of outline in hybrid is in the parent outline structure, not in the second pane text, making it a very effective structure for topical organization. One additional advantage of hybrid is that single pane can be used as single pane outliner with second pane used for notes or reference tracking.

File formats

Several file formats support an outline structure natively or encourage the use/creation of outline structures.

• XML - XML's purpose is to aid information systems in sharing structured data
• HTML/XHTML - outlines relatively trivial thanks to nested markup
• OPML - simple XML-based format designed for outlines, but also used for syndication feedlists
• OML - alternative to OPML
• RDF - (various formats) has web-oriented node & arc graph model, can be used for outline subset
• XOXO - dedicated HTML-based microformat for outlines
• CHM - standard Windows format for help, books, etc.

Desktop outliners

Name	Operating system	Notes
Acta	Mac OS 9	Single pane outliner, free to download
ActionOutline	Windows	Double-pane outliner. Multiple outlines per file, selected via 'worksheet-style' tabs.
AllMyNotes Organizer	Windows	Can password-protect file access, supports Skins. Free and Portable editions available.
Bonsai (Desktop Edition)	Windows	Designed to synchronise with the Palm OS version of Bonsai
Circus Ponies NoteBook	Mac OS X	Single-pane outliner designed to resemble a spiral bound notebook
Code Browser	Windows/Linux	folding text editor, can outline source code
Deep Notes	Mac OS X	Freeware single pane outliner. Only 1.7 megabytes, runs on OS X 10.4 or later.
Ecco Pro	Windows	Freeware outliner. EccoMV add-on for RTF pane.
GJots	Linux
GrandView	MS-DOS	Powerful single-pane outliner dating from the 1980s
Idea Cruncher	Windows	Minimalist two-pane outliner
In Control	Mac OS 7/8	Vintage outliner from Attain Corp. which could sort or filter outlines according to keywords or metadata attached to each topic
Jot+ Notes	Windows	two-pane outliner where the 2nd pane supports Rich Text formatting and embedded pictures and objects, such as spreadsheets. One can navigate not only via the topic hierarchy in pane one, but also via hyperlinks in the text of pane two.
Jreepad	Platform independent	Compatible with Treepad. Written in Java.
KeepNote	Windows/Linux/MacOS	Notes saved in HTML. Written in Python.
KeyNote	Windows	Mozilla Public License. No longer supported.
KeyNoteNF	Windows	Mozilla Public License. Evolution of KeyNote.
KJots	Linux
MORE[4]	Mac OS 7/8/9	Classic Mac outliner from the late 1980s & early 1990s
MyInfo	Windows	Two-pane, but can emulate basic one-pane outliner too
Leo	Windows/Linux/MacOS	Python application (use Tk for the UI)
Neomem	Windows	3-pane outliner. Website last updated July 2008.
NoteCase	Windows/Linux/MacOS	No longer supported.
NoteCase Pro	Windows/Linux/MacOS
NoteKeeper	Windows	Lightweight freeware two-pane outliner
Noteliner	Windows	Lightweight freeware outliner with todo capabilities, tagging & tables
OmniOutliner	Mac OS X	Fully featured single/double pane outliner with columns and extensive customisation capabilities
Opal	Mac OS X	Single pane outliner, essentially a port of 'Acta' to Mac OS X
OPML Editor	Mac/Windows	GPL
OrgMode	cross-platform	Emacs outlining mode
Outliner Lighto	Windows	Free software, console-based outliner written in FreePascal
Sain Outliner	Windows	Low cost, very simple single-pane outliner
Scrivener	Mac OS X; Windows & Linux beta	Flexible content generator for writers; powerful multipane outliner
SEO Note	Windows	Free lightweight two-pane outliner
The Guide	Windows	Free lightweight two-pane outliner
ThinkTank	MS-DOS	Early PC outliner, now abandonware
Tkoutline	Platform independent	Written in Tcl/Tk
ToDoList	Windows	Free (Eclipse Public License). Portable. Large number of node attributes. French and Spanish versions.
Tombo	Windows, Windows CE, Windows Mobile	Minimalistic. Regex search. GPLv2.
Total Text Container	Windows	Freeware 2-pane outliner
Treeline outliner	Windows/Linux	Free 3-pane outliner; 2nd pane shows details of highlighted node, 3rd pane lists details of its children
Treepad	Windows/Linux	Two-pane outliner. Free and paid versions.
TuxCards	Linux	Freeware 2-pane outliner
The Vim Outliner	cross-platform	Vim plugin
UV Outliner	Windows	Free, single pane outliner
Vault 3	Windows, Linux, Mac OS X, Android	Free Outliner. XML import and export. Optional 128-bit AES encryption.
Vim Outliner	cross-platform	Vim plugin
VOoM	cross-platform	Vim plugin, emulates two-pane outliner. Requires Python and Vim compiled with Python interface.
WhizFolders	Windows	Two-pane outliner
WikidPad	cross-platform	Wiki-like outliner.

Mobile Device outliners

Name	Operating system	Notes
Android Outliner	Android	Sync with Natara Bonsai on Windows desktop via USB or DropBox; due-date based filtering; supports multiple outlines. Under active development, with very user feedback-driven feature selection.
CarbonFin Outliner	iOS	Outliner for iPhone, iPod touch, and iPad. Web app with synchronization is also available.
Vault 3 for Android	Android	Outliner for Android devices (Android 2.1 or later). Desktop versions are also available (Windows, Linux, and Mac OS X).
Zeptoliner	iOS	Outliner for iPhone and iPod Touch.

Online outliners

This table shows a list of online, browser-based outliners categorised by the functionality they provide (see 'Design' above).

Name	Promote/ demote	Copy	Styling	Expose/ hide levels	Hoist	Search	Import OPML	Export OPML	Export other	Collaboration	Files
ActionManager	Yes	No	No	Yes	No	No	No	No	No	No	No
Checkvist	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	No
Knowcase	Yes	Yes	Yes	Yes	No	No	No	No	No	Yes	No
Loosestitch	Yes	No	Yes	Yes	No	No	No	Yes	Yes	Yes	Yes
Lucid	Yes	No	No	No	No	No	No	No	No	No	No
The Outliner of Giants	Yes	Yes	Yes	Yes	Yes	No	No	Yes	Yes	No	Yes
Tidylines	Yes	Yes	Yes	No	No	No	No	Yes	Yes	Limited users	No
Thinklinkr	Yes	Yes	No	Yes	No	Yes	Yes	Yes	Yes	Yes	No
WorkFlowy	Yes	No	No	Yes	Yes	Yes	No	No	Yes	Yes	No

See also

• Code folding
• Folding editor
• Desktop Wiki
• Personal information manager, List of personal information managers
• Concept mapping, Mind mapping, List of concept mapping and mind mapping software
• Notetaking, Comparison of notetaking software

References

1. ^ Robert S. Houghton (2005-12-31). "Outlining Tutorial for Microsoft Word". Ceap.wcu.edu. http://ceap.wcu.edu/houghton/EDELCompEduc/Themes/outline-word/outlineword.html. Retrieved 2009-02-18. 
2. ^ "How to create an outline in a document in a Word 2002". Support.microsoft.com. 2006-07-27. http://support.microsoft.com/kb/309365. Retrieved 2009-02-18. 
3. ^ "Overview of Windows Outliners". John.redmood.com. http://john.redmood.com/organizers.html. Retrieved 2009-02-18. 
4. ^ MORE

External links

• Comparison of desktop outliners
• Comparison of online outliners
• Overview of Windows outlining programs (at least 4 years old)
• Expanding Brain Outliner Wiki
• Outlines: The Do Everything Tool
• OutlinerSoftware.com, Discussion of Outliners