In ExxonMobil's technical jargon, all activities related to the exploration and production of natural gas and crude oil are referred to as 'upstream'.
The crude oil produced from the wells is transported 'downstream' via tankers and pipelines to the refineries in Rotterdam and Antwerp. This is where the various liquids and gasses that mineral oil contains are separated to make the products that ExxonMobil markets, such as petrol, kerosene, LPG, marine gas oil and diesel.
Chemicals are nature's building blocks. The chemical building blocks (or molecules) are transformed by creative scientists into countless products that we use every day.