Kryptonians are a fictional extraterrestrial race within the DC Comics universe that originated on the planet Krypton.

Members of a dominant sentient species of the planet Krypton are indistinguishable from Terran humans in terms of their appearance in their physiology and genetics, but they are vastly different.

In some continuities Kryptonians are difficult to clone because their DNA is so complex that human science is not advanced enough to decipher it.

The cellular structure of Kryptonians allows for solar energy to be absorbed at extremely high levels.

Krypto was the family dog in Jor-El's home and was used for a test flight of the rocket that ultimately brought baby Kal-El to Earth.

Also, in both Silver Age and Modern Age continuity, Kryptonians have more than one ethnic group, such as dark-skinned Kryptonians from Krypton's Vathlo Island that resemble Earth humans of West African, Negrito, Melanesian, and Indigenous Australian descent and a group from the continent of Twenx that resemble Earth humans of North African, Middle Eastern, Asian, Micronesian, Polynesian, Native American, and Latino descent.

Kryptonians use solar energy from yellow, blue, orange or white stars on the cellular and molecular levels to gain superhuman abilities.

[4] Superpowered Kryptonians are vulnerable to kryptonite, radioactive remnants of Krypton, magic and solar radiation from red and orange suns.

Self-grown crystals, both natural and synthetic, which covered the vast majority of their planet's surface gave their homeworld a bluish hue when viewed from space and underlay Kryptonian technology.

According to the Superman movie and sequels, a shape similar to the Latin letter "S" represents the House of El, for example.

It was worshiped by the Kryptonians as a deity (albeit in a more scientific and rational way as the giver and sustainer of all life on the planet).

According to one story, in which Quex-Ul had served his full sentence, 18 Kryptonian sun-cycles (amzeto) is about 25 Earth years.

The people of Argo City also survive Krypton's destruction due to an energy field surrounding it, although in most universes they either die soon afterward or are captured by Brainiac.