Each Narrative can, alongside the flow of bot-initiatives, have a selection of User initiatives. These are sub-dialogs that start with the user saying something - hence the name initiatives. These are typically used to supply answers to questions users might ask at any time in the dialog, or to let users take control over the dialog.
A key feature in Narratory is that the bot will continue where it was in the Narrative after a user inititative has been completed unless you do a goto to a different place in the dialog.
Here is an example of a user initiative where the bot simply replies to a question a user may ask (and then continues where it was in the flow of bot-initiatives):
Another example, where the user changes the direction of the dialog by going to a different part of the narrative using the optional goto parameter of the bot turn. Note that this overrides the default behavior of continuing where the bot was in the Narrative.