Charles F. Haanel (1866–1949) was an American author, philosopher, and entrepreneur. Born in Ann Arbor, Michigan, Haanel's timeless teachings on personal development and success have left an indelible mark on the self-help genre. His deep insights into the power of the mind and universal principles continue to inspire countless individuals on their journey towards unlocking their true potential.

Through his groundbreaking book, The Master Key System, and other notable works like Mental Chemistry and The New Psychology, Haanel continues to guide individuals on their journey to personal and professional mastery. His works remain a guiding light for those seeking to transform their thoughts into tangible success and fulfillment.