It was Marco Polo's book of his travels that introduced Europeans to China and Central Asia.
Although he was not the first European to travel to China, he was the first to write about his adventures and so it was his experiences that formed the basis of early European knowledge of the country.
For example, Marco Polo brought back the idea of paper money and some think his descriptions of coal, eyeglasses and a complex postal system eventually led to their widespread use in Europe.
Marco Polo's book inspired Christopher Columbus and other explorers to begin their own adventures. You can find the book under various different titles - Book of the Marvels of the World or The Travels of Marco Polo or Description of the World (in English), Livre des merveilles du monde or Divisament du monde (in French), and Il Milione or Oriente Poliano (in Italian).