Humans (人間 ningen?) are the dominant species of the Real World. Some Digimon get along with certain kinds of humans while others won't easily cooperate with them and some are able to channel their power. Some Digimon are also able to take on human forms. Also, it is possible that the God of the Digital World is a human.
Humans and digimon have a mixed track record of interactions. Some Digimon have been known to attack the humans in the real world, while some digimon befriend humans and even become partners to certain humans known as DigiDestined.
In many series, humans are able to assist their Partners in battle.
A "Tamer" can use "Digi-Modify" by swiping a card from the Digital Monster Card Game through their D-Power to give extra power or weapons to their Digimon Partner. A Digivolution card allows a Digimon to digivolve from their Rookie to Champion level, while a Blue Card allows them to digivolve to Ultimate level.
Some Tamers are able to biomerge with their Partners, allowing them to digivolve to the Mega level.
Digimon Data Squad
Every human possesses an aura-like "D.N.A." made from their emotions. By charging the D.N.A., a human is able to make their partner digivolve.
Digimon Xros Wars (manga)
Digimon Universe App Monsters
Digimon Story: Cyber Sleuth
When entering Cyberspace EDEN, humans are completely digitalized, including their minds, which become "mind data" (精神データ seishin dēta?). It is possible to hack someone's mind while in EDEN and learn their secrets. It is also possible to erase someone's memories, although never completely, or implant fake memories in someone. The EDEN Syndrome is caused by Eaters devouring a person's mind data, which causes their bodies to return to the Real World in a comatose state.
Digimon World: Next Order
In the Digital World, humans are pure data, and as such they can't get tired or feel hunger, unlike Digimon, who need to sleep and eat.
Notes and references