Art Diary

An art diary is a daily journal kept by artists, often containing both words and sketches, and occasionally including multimedia elements such as collages. Such books will frequently contain rough workings, in cartoon form, of ideas later to appear in finished works, as well as acting as a normal diary, by allowing the artist to record their day-to-day activities and emotions.
These diaries not only give art historians a valuable opportunity to explore the creation process of these finished works, but they are a useful biographical tool. Many famous artists are known for their art diaries - the sketchbooks of Leonardo da Vinci are probably the best known example.
See: http://en.wikipedia.org/wiki/Art_diary