Short answers, pulled from the story.
Zeami Motokiyo changed the course of Japanese theater in the year 1336 when he stepped onto a stage in Kyoto at the age of twelve. His performance alongside his father Kan'ami Kiyotsugu caught the eye of the seventeen-year-old shogun Ashikaga Yoshimitsu. This patronage transformed Noh from a folk tradition into a highly codified, aristocratic art form that has survived for nearly seven centuries.
The traditional stage of Noh theater is built entirely of unfinished Japanese cypress known as hinoki. It features no decorative elements to distract from the actors and includes a single pine tree painted on a panel called the kagami-ita as the only backdrop. The roof is independent and supported by four pillars named for specific roles such as the shitebashira for the principal character.
Five major schools exist today including the Kanze school established by Kan'ami and Zeami and the Hōshō school founded by Kan'ami's eldest brother. The Konparu school traces its lineage back to Bishaō Gon no Kami in the 14th century while the Kongō school and the Kita school were completed by Kita Shichidayū during the Tokugawa period. These schools function as guardians of secret documents and traditions passed down from ancestors.
There are approximately 450 different masks in Noh theater mostly based on sixty types each with distinctive names and specific uses. These carved objects of Japanese cypress transform the actor into a character of any gender age or social rank. The mask conveys emotion through the subtle tilting of the actor's head to reveal expressions like laughing or smiling known as brightening or appearing sad or mad known as clouding.
Jo-ha-kyū is a principle that governs the flow of time and energy in Noh performance meaning beginning breaking and rapid or urgent. In a traditional five-play program the first play is jo the second third and fourth plays are ha and the fifth play is kyū. This structure applies to songs dances and basic rhythms where the performance starts in a slow tempo gets slightly faster in the middle and culminates in a rapid urgent finale.
Nohgaku theater was inscribed on the Representative List of the Intangible Cultural Heritage of Humanity by UNESCO in 2008. This global recognition followed a period of financial crisis after the fall of the Tokugawa shogunate in 1868 and the subsequent Meiji Restoration. The Japanese Government designated Nohgaku as an Important Intangible Cultural Property in 1957 to afford legal protection to the tradition and its most accomplished practitioners.