Storybook is a free software program that helps you manage your novel.  Here's how the website describes it:

"Store all information about your characters and locations in one place. Then, use the included Storybook features for managing chapters, scenes, characters and locations, items and tags. A simple interface is provided to enable you to assign your defined characters, locations, items and tags to each scene and to keep an overview of your work with user-friendly chart tools. With the Memoria Tool each object can be followed in dependence on time."

Like most "free" software, it withholds a number of features - like the ability to export and print, rather a crucial one, or the ability to use it without being connected to the internet - unless you purchase the paid version.  This makes me slightly suspicious of its claim to be "open-source."  Surely the point of open-source software is that you have access to the source code to make modifications?

Basically, the website is a plea for you to purchase the paid version, Storybook Pro, at US$29.  Which isn't that much, at the end of the day, if you find it useful.  Can it beat good old index cards and blue-tac?  You decide.

Visit the Storybook website.