'The Book of Shadows' is the name for your Wiccan journal. It's your own creation, intended to reflect only your own - no one else's - personal goals, ideals and priorities. Its purpose is to guide you on your spiritual journey through Wicca, keeping you on the path of Wiccan principles and Wiccan spirit.
The Book of Shadows can be the place where you interpret your dreams or keep a log of your meditations and self-discoveries. It can also be where you preserve more practical information, such as how to perform rituals, how to invoke a god or goddess, or how to make amulets and other objects of magick. Whatever you choose to put in your Book of Shadows, it should always be meaningful to you and a source of inspiration.
It has been said that the name 'Book of Shadows' comes from an ancient Sanskrit guide for telling a person's future based on the length of his or her shadow.