Why the book is interesting today is that it still is important and the most authoritative work on how to value financial assets.
"Williams combined original theoretical concepts with enlightening and entertaining commentary based on his own experiences in the rough-and-tumble world of investment."
Williams' discovery was to project an estimate that offers intrinsic value and it is called the 'Dividend Discount Model' which is still used today by professional investors on the institutional side of markets.
Why the book is interesting today is that it still is important and the most authoritative work on how to value financial assets.