The "Red Book," officially known as the "Liber Novus," is a manuscript created by the Swiss psychiatrist Carl Jung between 1914 and 1930. It contains Jung's explorations of his unconscious mind through vivid illustrations and poetic text. The book serves as a record of his inner experiences and is considered a foundational work in analytical psychology. The "Red Book" was not published during Jung's lifetime and remained largely unknown until its release in 2009. It is significant for its insights into dream analysis, archetypes, and the process of individuation, making it a crucial resource for understanding Jung's theories and the development of modern psychology.