TiddlyWiki is a personal wiki and a non-linear notebook for organising and sharing complex information. It is an open-source single page application wiki in the form of a single HTML file that includes CSS, JavaScript, embedded files such as images, and the text content. It is designed to be easy to customize and re-shape depending on application. It facilitates re-use of content by dividing it into small pieces called Tiddlers. TiddlyWiki is an unusual example of a practical quine. This idea of producing a copy of its own source code that lies at the heart of TiddlyWiki's ability to independently save changes to itself. Quine is also the name of the unofficial TiddlyWiki application for iPhone/iPad. Applications TiddlyWiki is designed for customization and to be shaped according to users' specific needs, perhaps comparable to a high-level programming language. As such, it can be shaped into a wide and arbitrary range of special applications. Examples include niche note-taking applications, to-do lists, presentations, collections, authoring tools, personal databases, recipe collections, etc. Although there are many TiddlyWiki documents on the Web, the majority of TiddlyWikis reside on personal computers or in the cloud, or are exchanged over email, in a manner similar to word processing documents and spreadsheets. As a single HTML file, or saved as an HTA file in Microsoft Windows (allowing corporate IE lockdown to be bypassed), TiddlyWiki can be useful in corporate environments where red tape or IT resources might prevent the use of a wiki that requires a more complicated installation. TiddlyWiki has been used as a software framework to build specialisations. For example ... Interactive Historical Atlas of the Disciplines is an Interactive Historical Atlas of the (Knowledge) Disciplines SocialText uses TiddlyWiki as a part of their unplugged feature. Tiddlers TiddlyWiki introduces the division of content into its "smallest, semantically meaningful, components", referred to as tiddlers. Each tiddler is stored inside an HTML division that contains the source text and meta data in wiki markup. The purpose with this division is to enable easy re-use of content for different narratives and in different contexts. For example, this section ("Tiddlers") could be a tiddler. In the TiddlyWiki user interface it would appear as it appears here but as a separate "note" visually distinct from other tiddlers. The underlying HTML source code (which is not typically directly viewed or modified by end users) would be something like: <div title="Tiddlers" modifier="John