Price of a commodity is determined by market demand and market supply of a commodity, (i.e. industry is the price maker).
An individual producer/firm has no role in the determination of the price of the commodity (firm is a price taker). No individual seller or buyer can influence the price of the commodity.
DD and SS are Market demand and market supply curves intersecting at E. OQ quantity (Equilibrium Quantity) would be offered for sale and demanded by the buyers at OP price (Equilibrium Price) per unit. The industry is in equilibrium.
