Aether
It’s there everywhere all around you. A form of magical energy that infuses all things. It’s usually elementally attuned. Crystals form from solidified Aether, and are often seen dotting the landscape or being mined out of the ground for use in many enchantments and even technological constructions.
Mana
Aether that has been gathered into a living being’s personal aura. Utilized especially in casting White and Black Magic.
According to Sanctuism, being able to harness larger amounts of Mana means you are closer to the Heavenly Mother.
Psionics
A form of magic that is conducted through force of will and thought, instead of elementals. Though Mana is usually consumed to fuel it, the individual’s mental strength is the true power source of anything associated with psychic abilities. It’s a common stereotype that Psionics like to act as “mind readers” and barge into people’s thoughts, but most do not have this ability without a fully willing partner.
Mako
Liquidized substance that is extraordinarily high in Aether. It is present deep underground, only occasionally bubbling to the surface. Huge reactors invented by Shinra Corp. were built to harvest this and convert it to electricity. However, this has side effects including environmental damage and even the mutation of wildlife into monsters (and monsters into scarier monsters), so the use of Mako Reactors has been recently outlawed in most places.
Some believe Mako to be the blood of the planet itself, or contain spirits of the departed, or both. This is often referred to as the Lifestream theory.
Avalanche, a loose group of environmentalists, strongly opposes all use of Mako based on the Lifestream theory. Shinra Corp. has labeled Avalanche as a terrorist organization.
Magitek
A fancy word that just describes the use of magical substances (crystals, materia, etc) to fuel or assist machines.
Conventional Electrics
They exist, but followed a different history and development. For instance, coal was never very popular as an energy source because aether crystals could be mined instead. Nuclear power is theorized to be possible but still considered science fiction. Computers exist, but they’re a bit early-2000s - yet drones and semi-intelligent robots also exist thanks to Magitek.