What did da vinci write in vernacular?

Leonardo da vinci primarily wrote in Italian, the vernacular of his time, particularly in his notebooks and treatises. His writings included observations on art, science, anatomy, and engineering, aiming to make complex ideas accessible to a broader audience. Notable works like "Trattato DELLa pittura" (Treatise on Painting) showcased his thoughts in the vernacular, reflecting his desire to communicate effectively with fellow artists and thinkers of his era. This approach helped democratize knowledge during the Renaissance.