The article discusses Piero Sraffa's theory of price, which challenges traditional ideas about how prices are determined. Sraffa's key works include a 1926 article on Marshallian price theory, a 1951 introduction to David Ricardo's works, and his 1960 book "Production of Commodities by Means of Commodities." His theory emphasizes factors like relative price, joint product, labor time, and wage share. Sraffa's theory differs from Post Keynesian theory, highlighting unique perspectives on price determination.