According to ancient Indian mythology, Kartikeya (also known as Subramanya, Skanda or Muruga) is the son of Shiva and Parvati, and the brother of Ganesha. Given he came out of Shiva’s third eye, he is the incarnation of pure wisdom and vision. He was born to destroy the demonic forces of the world, and therefore came from the seed of Shiva who embodies the transformational and dismantling aspect of existence.
Six-headed, twelve-armed and seated on a peacock, Kartikeya is the symbol of empowerment and valour. He also denotes supreme knowledge, which alone can destroy the nescience of ignorance. (...) The peacock stands for the diversified and multifaceted universe. Skanda has conquered the materialistic world of pride, egoism and vanity and thus rides on the peacock. (...) The peacock symbolises the mental equipoise of the liberated person, who is capable of keeping balance between the material and spiritual. When mental equipoise is achieved, the mind becomes content and peaceful. The spear or Vel is pointed at the end and very long. It is a symbol of the mind that has to be single-pointed if it wants to slay the demon of ignorance. (Extracts from “The Lilas of the Sons of Shiva” by Vanamali)
He is sometimes depicted with weapons including a sword, a javelin, a mace, a discus and a bow although more usually he is depicted with a sakti or spear. The javelin is used to symbolize his far reaching protection, his discus symbolizes his knowledge of the truth, his mace represents his strength and his bow shows his ability to defeat all ills. His vehicle is a peacock which stands for the diversified and multifaceted universe. Skanda has conquered the materialistic world of pride, egoism and vanity and thus rides on the peacock. A pious bird that grips with its feet a serpent, which symbolizes the ego and desires of people. (wikipedia)
Kartikeya is the god of breaking code. He is is activating, protecting and a bringer of divine order. Above all, he is commander of the the army of gods.
The two great forces in Nature are gravity and electromagnetism. Ganesha is the force of gravity. The second great force is electromagnetism and Kartikeya is the god of this force. His power is electric. He instigates revolutionary changes and then brings order out of the chaos. His Shakti Vel or spear of power, works deeply within us like the powerful force that binds electrons and neutrons together. This power emanates from his spear like energy expanding through the universe in the form of radio and light waves. (...)
There are various ancient references in Vedic texts. Kartikeya means "of the Krittikas". After Shiva's son appears on the banks of the river Ganges, he is seen by the six of the seven brightest stars cluster in the night sky called Krittikas in Hindu texts (called Pleiades in Greek texts). These six mothers all want to take care of him and nurse baby Kartikeya. Kartikeya ends the argument by growing five more heads to have a total of six heads so he can look at all six mothers, and let them each nurse one. The six heads also stand for his virtues enabling him to see in all the directions — an important capacity that ensures he counters all kinds blows that could hit him. (Illustrated Encyclopedia of Hinduism)
Note: All creation is contained in the trimurti / triad of deities: Brahma, Vishnu, Shiva, representing Creation, Maintenance, Dissolution respectively. This trinity is also contained in Om. Basically, the entire Creation is contained in Om. This is the essence and also the secret of Om that Kartikeya narrated to Lord Shiva, according to one of the ancient legends.