What is perfect competition term?

Perfect competition refers to situation when there is no barrier imposed to sell, everybody has equal rights to sell the product, All firms sell an identical product . All firms are price takers (they cannot influence the market price of their product). Market share has no influence on prices.
Perfect competition is
the most competitive market imaginable in which everybody is a price taker. Firms earn only normal profits, the bare minimum profit necessary to keep them in business. If firms earn more than this (excess profits) other firms will enter the market and drive the price level down until there are only normal profits to be made.