Jor-El was a respected scientist from Krypton and husband of Lara-Lor Van and older brother of Zor-El. He is father of Kal-El, who he sent to Earth so he could save him from the destruction of Krypton. Kal grew into the superhero Superman.
Jor-El was a member of the Science Council of the planet Krypton, who discovered that the planet and its sun are on the verge of destruction. However, his warnings to the Science Council fell on deaf ears, as they considered this to be inciting sedition. Earlier on, Jor-El was involved in the sentencing of three dangerous criminals, General Zod, Non, and Ursa, for the crime of inciting sedition against the government and banished them to eternal imprisonment in the Phantom Zone amid threats from General Zod that one day his adversary and even his heirs will bow down before him.
Undaunted by the ignorance of the Science Council, Jor-El built a star ship for his infant son Kal-El to travel to Earth in, placing within the ship a green glowing crystal and an energy module containing the last remaining energies of Krypton. Lara sees the Earth as being primitive and that Kal-El will be a stranger among them, but Jor-El assures her that his son shall never be alone. As they watch the star ship rise into the sky and depart from Krypton, the ground crumbles underneath their feet and everyone else's until both Krypton and its sun explodes.
About 18 years after reaching Earth, Kal-El who became Clark Kent was summoned by the green glowing crystal to travel to the Arctic Circle and cast it into the sea from where it created a Kryptonian-style structure called the Fortress of Solitude. Inside, Clark activated a holographic representation of his biological father Jor-El, who taught his son the true nature of himself and his true name of Kal-El, spending 12 years teaching his son everything the memory crystals have recorded. At the end of the teaching, Kal-El now stands in the uniform of a superhero that the world will call Superman, bearing the family crest of El as a symbol upon his chest as did his real father before him.
After Lois Lane discovers Clark is Superman, he takes her to the Fortress of Solitude where he confesses his love for her before they spend the night together. He later confides with the hologram of Jor-El about his desire to be with her. Jor-El criticizes his desire as being selfish, but Superman asks how much good has he done would be good enough to allow him some form of happiness with someone else. Unable to sway his son to think otherwise, Jor-El tells him that the only way he can do that is to live as one of the humans, without any of his powers, and shows him the molecular chamber that harnesses the power of Krypton's red sun that will remove his powers forever. Believing that his love for Lois is worth the cost, Superman steps into the chamber as Lois watches it strip away his powers, leaving him as a human being.
After General Zod's arrival, Clark realizes how much the world needs him as Superman, he returns to the Fortress alone and pleads with the spirit of Jor-El his father to restore what he had given up. His father's spirit appears again and this time merges with his son, fulfilling what Jor-El had said before he sent his son to Earth: "The son becomes the father, and the father the son."