In 1811, at the age of 51, Hokusai changed his name to "Taito" and entered the period in which he created the "Hokusai Manga" and various "etehon", or art manuals. These manuals beginning in 1812 with "Quick Lessons in Simplified Drawing", were intended as a convenient way to make money and attract more students. The first volume of "Manga" (meaning random drawings) was published in 1814 and was an immediate success. By 1820, he had produced twelve volumes (with three more published posthumously) which include thousands of drawings of objects, plants, animals, religious figures, and everyday people, often with humorous overtones.