John Neff is a well-known American investor and fund manager, recognized for his successful investment strategies. He is best known for managing the Vanguard Windsor Fund, which he led from 1960 to 1995. Neff's investment philosophy focused on value investing, emphasizing the importance of buying undervalued stocks with strong fundamentals. Neff's approach often involved a long-term perspective, allowing him to weather market fluctuations. His strategies have influenced many investors and contributed to the broader field of investment management. Neff's legacy continues to be studied by those interested in effective investment techniques and market analysis.