In TiddlyWeb, an instance is a single collection of data, the store, with a (potentially empty) configuration. There can be any number of instances on any machine.

In most cases an instance is manifest in the filesystem as a directory containing the store, tiddlywebconfig.py and any plugins used in the instance.

In order to create a new instance, make or change to the directory where you plan to have the instance and do any of the following:
Note that the above only creates a very basic TiddlyWeb instance.
The twinstance command can be used to spawn a preconfigured TiddlyWebWiki instance:
$ twinstance myInstanceDirectory