Petroleum coke tends to be considered as part of the coal ‘market’ but, as the name implies, it is in fact a by-product of oil refining. It is exported from those areas where major refineries exist in particular from both coasts of the USA including the US Gulf; Europe and Japan are the major importers. It is produced in various grades depending upon the design of the refinery and is not the most popular of cargoes with owners. Some types are granular (up to about 5mm) and are rather oily whilst others are very fine which cause a dust problem. It has several uses because it is a source of almost pure carbon and one of its principal applications is in the manufacture of electrodes for use in the refining of aluminium. Grain. As it applies to ocean transport, grain includes wheat, rye, corn, sorghums, barley, oats, rice and oilseeds (the latter although not technically ‘grain’ is considered such from a chartering point of view). A pattern of grain trading has emerged during the 20th century, main producers being China, Russia, India, The United States, Canada, France and Argentina. Much of this production is needed close to home, however, and major exporters are the United States, Canada, Australia, Argentina and France. Major importers at present are Japan, China, the EEC, North African countries and the Middle East, Brazil and, above all, Russia. In addition, there are specific emergency trades developed to areas of the world where local famines and disasters occur, often organised by the World Food Agency, part of the United Nations. The largest phenomenon of the post-war decades, however, has been an ever-growing trend in former developing nations, as their prosperity has increased, to refuse to be content eating bread, rice or maize as a staple diet and to seek instead meat, or meat products, poultry and eggs. This evolution, translated into transportation and grain logistics, has created fundamental changes in trade.