The term M-C-M is used to explain how the capitalists build their wealth and keep it steady. M(Money) C(Commodity) M(More Money).

The “M” stands for the business owner using their starter money to invest in commodities. They get the money from previous work they’ve done. The “C” stands for the business owners using their money to purchase materials, machines, and labor power. The final “M” stands for more money, the things that are produced are sold and labeled at a higher price than how they originally purchased it for, basically selling it for more than they invested into it. The money they make is from the employees creating higher value products, but getting paid less; surplus value.