PetroChina Company Limited is a China-based company principally engaged in the production and distribution of oil and gas. The Company mainly operates through four business segments. The Exploration and Production segment is principally engaged in the exploration, development, production and sales of crude oil and natural gas. The Refining and Chemical Products segment is principally engaged in the refining of crude oil and petroleum products, as well as the production and sales of basic petrochemical products, derivative petrochemical products and other chemical products. The Sales segment is principally engaged in the sales of refined petroleum products. The Natural Gas and Pipeline segment is engaged in the transportation and sales of natural gas, crude oil and refined petroleum products.