Pokémon (Japanese: ポケットモンスター Pocket Monsters; ポケモン Pokémon for short) are 248 (As of Pokemon X Y, it is known there are at least 654) known species of creatures that inhabit the Pokémon world, however, it is implied that there are more waiting to be discovered. Inherent to them are several fantastic powers not demonstrated by most real animals, such as the manipulation of electricity or fire. Pokémon are shown to exist instead of animals in their world, although animals are also seldom seen in older media. While most Pokémon resemble animals and may behave like them, there are many that do not resemble animals at all; taking on other forms such as plants, inanimate objects, machines, human-like forms or other more enigmatic and exotic appearances. Pokémon inhabit an extremely diverse range of habitats, ranging from the driest deserts to the lushest jungles, the deepest oceans to the highest mountains and everything else in-between, even space and other dimensions. Pokémon take up various ways of living in those places. However, all can be befriended and made into potential allies.
Many Pokémon are known to evolve from or into other Pokémon, a process that typically makes them larger and stronger, and could be seen as the equivalent to "growing up". Pokémon typically know several techniques that they can use in battle or elsewhere, either to defend themselves or their Trainer, or to perform a task. In the anime, most Pokémon are known only to say their name. In the games, each Pokémon has a distinct voice associated with each species.
Pokémon have been, from the very beginning, spoken of as friends and partners to the humans of the Pokémon world, used to help with various tasks from constructing buildings to exploration. Many people in the Pokémon world take Pokémon with them on a journey to gather Badges and compete in the various Pokémon Leagues as Trainers, using them in battles against Pokémon both owned by other Trainers and found in the wild.
Pokémon are typically found in one of four manners: encountering them in tall grass, finding them in caves or ruins, going fishing for them, or trading with an NPC. These are often joined by several more ways in which to encounter Pokémon, such as surfing on water, headbutting trees, or using the Poké Radar.
Pokémon are creatures with distinctively more anthropomorphic qualities than normal animals, with several even able to speak. Some Pokémon have the ability to speak the dubbing language instead of their own names. They also seem to be able to mostly understand human language, while most humans can't understand Pokémon speak, although there are a few who claim they can.
The anime has given a more in-depth history of human interaction with Pokémon than is given by the games: Poké Balls, for example, have not existed forever, and are in reality an apparently recent development, with one owned by a young Professor Oak being shown to be vastly different than ones used in modern times.
Prior to the invention and mass-production of Poké Balls, people tended to use hollowed-out Apricorns, native to the Johto region, to capture Pokémon, while even further back, Pokémon were not known as "Pokémon" at all, but as "magical creatures" (Japanese: 魔獣 majuu). In these times, many Pokémon were apparently feared because of their powers, sometimes so great that the most powerful of these monsters passed into legend and were often seen as deities in their own right.