Class M planets are characterized by fertile lands, temperate climates and big oceans. They are also the most common planet type. This makes them the main source of food and water in the universe. They depend on a steady supply of energy.
Class IEditThe surface of Class I planets consists for more than 95% of ice. This makes them the ideal producer of water. Like Class M planets, they depend on energy.
Class D planets are essentially deserts. The average surface temperature generally exceeds 50°C. Water can only be found in oases, accessible only to a small part of the population, so it must be imported. The desert planets are inhabited by previously primitive cultures, still ruled by powerful Sheiks. They collect Gem Stones and would disappear without them. Energy is not needed on these planets as all work is done by hand or using simple machines.The innate inhuman conditions on these planets are reason for factions to turn a blind eye when it comes to slave trading. (Official faction standpoints are still "illegal", but there is little control to uphold it.)