From the introduction:
The Thu’um, also called the Storm Voice or simply the Voice, is a form of magic inherent in most Nords and some others which uses the words of the language of the Dragons to form “Shouts”, the equivalent of spells, of immense power. The word actually means “shout” in the Dragon language. The Nords believe that Kyne, the embodiment of the wind who is viewed as the Nordic aspect of Kynareth, breathed onto the land at the Throat of the World to form them. As such, the Nords believe that their voice and breath is their very essence, and that channeling this life essence is how the Thu’um operates.
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