The Little Book of Common Sense Investing, written by John C. Bogle, is a guide to passive investing and the benefits of index funds. Bogle, the founder of Vanguard Group, advocates for a low-cost, long-term investment strategy that tracks the performance of the overall market. The book explains the concept of indexing, highlights the advantages of diversification, and debunks common myths about active investing. It provides practical advice on how to build a low-cost portfolio and achieve market returns. The Little Book of Common Sense Investing is a must-read for anyone looking to simplify their investment approach and maximize returns.