Earl Nightingale was an American radio speaker and author, best known for his work in the field of personal development and motivation. Born on March 12, 1921, he gained fame for his inspirational recordings, particularly the classic audio program titled "The Strangest Secret," which emphasized the power of thoughts in shaping one's life. Nightingale co-founded the Nightengale-Conant Corporation, a company that produced and distributed personal development audio programs. His teachings focused on success, goal-setting, and the importance of a positive mindset, influencing countless individuals seeking personal and professional growth throughout the 20th century.