A composition, or comp, combines two or more tanks to achieve an alternate presentation or tool for managing the content in the tanks.

In one of the tanks in the comp there must be a tiddler called app. When the comp is loaded, the app tiddler is sent to the browser and used as the HTML starting point of a single page app.

This is the mechanism that supports using loading tiddlers in TiddlyWiki Classic and TiddlyWiki Five.

At this time there are two ways to create a composition. An advanced option is to use the API to create a recipe. A more simple option works as follows:

• Visit your dashboard and follow one of the links in Available Compositions.
• Using the "This tank is composable" interface, choose a name and a tank to compose with.

The comp that is created will be owned by you. If the tank you compose with is readable by others then the comp you create will be visible to them in lists such as recipes. Permission to creating and edit content is dependent on the policies of the tank you choose.