Digimon (デジモン Dejimon?) are fictional creatures from the Japanese Digimon media franchise. They are central to several anime series and films, manga, video games and other merchandise. The word "Digimon" is invariable in the plural, and stands for "Digital Monster" (デジタルモンスター Dejitaru Monsutā?). Digimon include almost all the creatures that reside within the fictional parallel universe called the "Digital World." There are many different species of Digimon, as well as unconfirmed and new generations of Digimon yet to be revealed. The rate of new Digimon species continuously increase as the Digital World expands each year.
Digimon hatch from eggs called Digi-Eggs (デジタマ Digitama?). They age via a process called "Digivolution" which changes their appearance and increases their physical powers. Some Digimon act feral, like wild animals. Most, however, possess human intelligence, speech, and personality traits. It was mentioned that, if a Chosen Digimon were to be seperated from their partner, then they would start to become weaker. An example of this is Yolei Inoue's partner, Poromon. When Yolei was away in Kyoto, Poromon began to feel weaker each day. The first Digimon anime introduces the Digimon life cycle: they age in a similar fashion to real living organisms, but do not die under normal circumstances because they are made of reconfigurable data. Old Digimon and Digimon who receive fatal wounds dissolve into infinitesimal bits of data. The data then recomposes itself as a Digitama and the Digimon goes through its life cycle again. Digimon who are reincarnated in this way will sometimes retain some or all their memories of their previous lifespan. However, if a Digimon's data is "downloaded" as demonstrated in Digimon Tamers, in which all the data of a dying Digimon is absorbed by another, or if the data is completely deleted or destroyed, they will permanently die. In special cases, some Digimon do not get reincarnated despite their data still existing. A famous example is the Wizardmon of the first season, who's data remained in the Real World following his death, and thus was not reconfigured.
Digivolution Digivolution is the process by which a Digimon "ages" and grows up into larger and more powerful forms. Although the word "Digivolution" is short for "Digital Evolution", Digivolution is in fact more similar to metamorphosis in that Digivolution changes a Digimon from one form to another (which can sometimes be very different in appearance) very quickly. Digivolving for Digimon is similar to aging for humans - it is generally a one-way journey whereby a Digimon will grow into a new form as they age and gain battle experience and data. However, moving from one form to another becomes progressively more difficult. Therefore, very few Digimon will ever naturally Digivolve into their final most powerful forms.
However, for the Chosen Digimon who are partnered with DigiDestined humans, Digivolution becomes far more flexible. Digimon who form bonds with a human are able to digivolve more easily, generally through the use of a Digivice owned by the human. In such cases, the Digimon is channeled large amounts of energy and is therefore able to instantaneously digivolve to a higher level. However, these Digimon will generally de-digivolve back into a lower form after a fight. Digimon partnered to humans are also commonly able to use special forms of Digivolution not naturally available, giving these Digimon many different forms. These include Armor Digivolution, and Biomerge Digivolution (fusing with their human partners).
In some cases, Digimon have also been granted the ability to digivolve into higher forms by other, very powerful Digimon. In Digimon Tamers, Impmon was able to digivolve into his mega form by using power given to him by Zhuqiaomon.
During Digivolution, a Digimon's appearance changes, and many of its other classifications (such as attribute and family) also sometimes do. The Digimon's fighting ability increases significantly, and the resulting Digimon is considered to be of a different species. However, Digimon species which are connected through Digivolution are generally similar in appearance. For example, Agumon is a small dinosaur-like Digimon; his Digivolved form is Greymon, a much larger fully-grown dinosaur; and then MetalGreymon, a large armored and winged dinosaur. However, Digimon can sometimes Digivolve into forms that appear very different. Salamon is a dog-like Digimon, but Digivolves into Gatomon, a cat-like Digimon. Gatomon is able to further Digivolve into Angewomon, a bipedal winged angel.
Gender-  The gender of Digimon is a complicated topic. It has officially been stated in at least two places that Digimon do not have "gender" - one in Chiaki J. Konaka's official Digimon Tamers character design notes for Renamon, and again, by Renamon herself in an episode of the series, when she states that "Digimon aren't divided into gender."
This, however, is not congruent with the portrayal of the creatures in the series. Many Digimon, especially those of humanoid design, appear specifically male or female, and most Digimon speak with gendered voices. Moreover, characters regularly referred to Digimon as either "he" and "she" - a specific example of this is Jijimon and Babamon, who are called a married couple. Konaka points this out, when he says that "...gender seems fairly easy to identify in Digimon." Some Digimon even have names composed of gender-specific nouns (for example, Angewomon and LadyDevimon).
This is most likely the end result of semantic confusion. While the words "gender" and "sex" are often used interchangeably, they have vastly different meanings academically. "Gender" is the social construction by which individuals are defined as masculine or feminine based on their mentality; Digimon, inarguably, have this. On the other hand, "sex" is the biological condition of being physically male or female. Although a comparatively small number of Digimon display certain secondary sex characteristics (body hair, breasts), it would appear that this is what Konaka is attempting to say that Digimon do not have - that they lack the biological classifications of being male and female, do not have physical features that distinguish the males and females of species (for example, the "female" Biyomon of Digimon Adventure and the "male" Biyomon of Digimon Savers are visually identical, in addition some digimon that are treated as one gender may digivolve into a digimon that appears to be the opposite gender, for example the said female Biyomon later digivolves into a Garudamon, which can vocally sound either male or female, but will always have a masculine body), and do not sexually reproduce.
In Xros Wars, at least, the stance on gender is clear: Digimon have gender, and can form romantic relationships and families just as well as humans. Cutemon is driven by the search to find and rescue his biological parents, and at one point angrily declares that he is a boy when confused for a girl. The heroes of the Forest Zone, Stingmon and Lilamon are also in a committed relationship. Furthermore, while trying to convince Taiki to stay in the Digital World and help him become King, Shoutmon gets Lillymon to dance alluringly for Taiki, and calls her a "hot babe".
Name-The name of a Digimon species is usually based on its form, and may be a pun. For example, Hyokomon's name and design are derived from the Japanese onomatopoeia for unsteady steps (「ひょこひょこ」 "Hyokohyoko"?), as well as the Chick (雛 Hiyoko?). The species's name always ends in "-mon". Digimon are generally not given individual names, and are instead simply referred to by the name of their species. So the word "Agumon" actually refers to a Digimon species, and not a single individual Digimon. The Agumon in Digimon Adventure and the Agumon in Digimon Savers share the same name because they are of the same species. However, they are not the same individual, and are different in appearance and voice.
When a Digimon Digivolves and assumes a new form, its name changes to match the species of its new form. However, it is still the same individual, despite having a different name.
The exception to this is the Digimon manga series V-Tamer. In this series, Digimon were given individual names. The main Digimon character in this series was a Veedramon named Zeromaru,or Zero for short. Although Zero was able to Digivolve into more powerful forms such as AeroVeedramon and UlforceVeedramon, its name remained as "Zero" (although its species and form changed). The Digimon Arkadimon (also from the V-Tamer series) is also an exception because all it's 6 Digivolution forms share the same species name. So that "Arkadimon" is both the name of this character, and the species name for all of its 6 Digivolution forms.
Classification-Digimon species are given many different classifications. With the exception of level, these are generally only important in the Digimon card game, and play a very small role in Digimon anime. LevelEdit Digimon species are classified by their "digivolution level". Digimon generally hatch out of Digi-Eggs (デジタマ DejiTama?, lit. "DigiTama") as Fresh level Digimon, the lowest and weakest level, roughly equivalent to human infants. Most Digimon of this level are small and do not have well-defined body parts.
Eventually Fresh Digimon digivolve to the In-Training level, a slightly bigger and more complex form that generally still has undefined body parts.
In the anime, most digimon encountered are of the rookie or champion level, ultimate and mega-level digimon are rarer. Digimon of one Digivolution level are generally far stronger than Digimon of the previous level. There are exceptions where a Digimon has been able to defeat an opponent of a higher level. There are also cases, such as with Lucemon and Arkadimon, where a Digimon is far more powerful than what its actual Digivolution level would lead one to think.
For most Digimon, there are six Digivolution levels:
Fresh or Baby (幼年期I Younenki I?, lit. "Childhood I"), officially translated as "Baby I" In-Training (幼年期II Younenki II?, lit. "Childhood 2"), officially translated as "Baby II" Rookie (成長期 Seichouki?, lit. "Youth"), officially translated as "Child" Champion (成熟期 Seijukuki?, lit. "Adolescence"), officially translated as "Adult" Ultimate (完全体 Kanzen-tai?, lit. "Perfect form"), officially translated as "Perfect" Mega (究極体 Kyuukyoku-tai?, lit. "Ultimate form"), officially translated as "Ultimate" There is also a level beyond the standard Mega, known as Super Ultimate. There are also other levels, the most notable being "Armor" and "Hybrid". The "Armor" level appeared in the Digimon Adventure 02 series, and is reached when a Rookie (or Champion Level in Gatomon's case) Digimon uses a Digi-Egg to Digivolve into an Armor Digimon. The "Hybrid" level contains several sub-levels, and is exclusive to the Digimon Frontier series for Digimon who are formed by "Spirit Digivolution".
Mode Change-  There are some Digimon species who have multiple "modes", and are able to "Mode Change" between them. Often, this involves going from their normal form to a special mode that is more powerful in some way. For example, Beelzemon and Beelzemon Blast Mode. A Digimon's different modes are generally very similar in appearance (in this case, Beelzemon Blast Mode is simply Beelzemon with a giant blaster on one arm, green eyes instead of red, and two pairs of wings (two large, two small)). Another example is Gallantmon and Gallantmon Crimson Mode where Gallantmon Crimson Mode is Gallantmon with red armor, a spear and sword, and the cape being replaced by angelic wings. Different modes of a Digimon are generally considered to be the same species. This is because a Digimon who goes through a Mode Change remains at the same Digivolution level (Imperialdramon, Imperialdramon Fighter Mode, and Imperialdramon Paladin Mode are all Mega level Digimon in all appearances, despite going through two Mode Changes), and retain the same name (except with a suffix giving the name of the new mode).
Although Mode Changing does not result in a change in a Digimon's species or level, it is considered a form of Digivolution. There is but one exception to this, Lucemon. In Frontier, the Mode changes Lucemon goes though in the ending episodes of the season change his form and level; going from his regular Rookie level, to an Ultimate level in Chaos mode, and then to Mega Level in Larva and Shadowlord modes, this further proves that a mode change is a type of Digivolution.
In Digimon Savers, the transition to Burst Mode is called "Burst Evolution", showing that this Mode Change is also considered to be a form of Digivolution.
Attributes-  All Digimon species are classified into four attributes - Data, Vaccine, Virus and Variable. Most Digimon fall into the first three categories, the fourth "Variable" category is exclusive to Hybrid Digimon. There is also one other group "Unknown", for Digimon who either do not have an attribute, or are classifed as being "Unidentified". These attributes have a Rock, Paper, Scissors arrangement where Virus is generally advantaged against Data, Data is advantaged against Vaccine and Vaccine is advantaged against Virus. However, these attributes don't play a very important role in Digimon fights. A Digimon can generally defeat an opponent regardless of attribute if it is stronger than the opponent in Digivolution level and experience.
Most evil Digimon are of the Virus attribute (although not all Virus Digimon are evil; Wormmon and Guilmon are the most notable exceptions), and Vaccine Digimon are generally considered to be "good". In the Digimon card game, some Digimon species can have more than one attribute. For example, most cards for the Digimon species "Agumon" are of the Vaccine attribute, but there is a Virus version. Gabumon has versions for all three attributes. Different attribute versions of a Digimon are sometimes of different colors. An example of this is where the standard MetalGreymon has orange skin and red hair, but his Virus form has blue skin and darker hair.
Family- Digimon in the card game are also classified into 10 different "Digimon families". These classifications are mostly trivial. They seldom appear in the Digimon anime series, except for the latter part of the first season, when "Wind Guardians" and "Deep Savers" are mentioned during the Dark Master saga. They have little bearing on actual gameplay in the card game. Each Digimon family have a different colored background in the Digimon card game, and the Digimon within a family usually have something in common. For example, the Dragon's Roar family consists of Digimon who resemble dragons.
These families become more important in the Digimon World Data Squad and Digimon DS games, where these families help determine what attacks Digimon are strong or weak to, as well as influence Digivolution requirements.
Type- As another form of classification, all Digimon species are given a "type". This generally describes the physical appearance of the Digimon. So for example, Agumon is a "Reptile type" Digimon, whereas Angemon is an "Angel type" Digimon. Some types, such as "Insect type", include dozens of Digimon, whilst others, such as "Ancient Insect type" are unique and belong to only a single Digimon (in this case it's AncientBeetlemon.) A Digimon species is generally classified into only one "type". Like the "Family" classification, "Type" is considered to be a fairly trivial and unimportant classification. It is referenced occasionally in the anime, and has some minor gameplay effects in the Digimon card game.