There are two major types of trained psychic skills.
SorcerySorcery is split into shaping and channeling and involves the manipulation of one's Life-Force. These are effects that have been discovered by both trial and error and careful research and passed on for centuries. They can reproduce many Talents, but those born with abilities are capable of higher levels of efficiency (assuming they put as much effort into that particular ability.)
Shaping is a more ritualistic, careful and slow manipulations of Life-Force to reproduce specific effects. Most shapers are focused on more civilian issues. This includes those that produce psychic tools of various types, like the various quartz talismans favored by humans; exorcists that treat curses and other Life-Force related maladies; researchers; some divinations and quite a few other things.
Channeling are the martial arts of the psychic world. It focuses on the quick and blunt use of Life-Force to enhance the body, create defensive auras and unleash blasts of pure Life-Force. In practice, it can't produce fire or lightning the way a Talent can, nor is a channeller technique to increase strength going to match a Talent born with superhuman strength (assuming both psychics put the same effort into the development of the ability). However, channellers are able to produce a wide range of effects. Also, people don't train in channeling without intending to be warriors and that mindset is an important difference from someone just born with an ability.
To be considered a full sorcerer, one must have practiced both shaping and channeling, though most sorcerers focus more on one facet than the other.
MagicMagic is the borrowing of a psychic ability that belongs to some other being. It includes the Low Magic practiced by a magician and the High Magic practiced by a magus.
Magicians practice magic by taking samples of genetic tissue from other people, usually blood. Since every sentient is at least minimally psychically active, any blood can be useful to create some sort of potion, but the blood of Talents is more prized since it can be used to approximate their abilities. Most magicians are harmless enough and focus on practical day to day sort of recipes. They frequently pay for blood donations and charge for their services to create whatever recipes necessary. This can be a potion to keep one calm on the day of an important meeting, made from the blood of a good negotiator; or it could be a potion crafted from the blood of someone who survived a particular disease. However, there have been more than a few magicians that have engaged in more unethical activities such as human sacrifice in order to more permanently acquire someone's Talent.
Unlike most mortals, Gods and Demons have minds that can be accessed much more easily. Where as trying to reach deep enough into the mind of a mortal to access their psychic abilities would typically kill the person you are borrowing from (see the note about human sacrifice above), a God or Demon would barely notice when someone borrowed a power from them. However, there are prices involved. Using an Immortal from Yomi (mostly Demons and a few Gods) as a source for a spell would end up with you owing one of them a "favor". Using an Immortal from Nirvana (mostly Gods and a few Demons) as a source for a spell would end up that Immortal gaining your surface thoughts and perceptions for as long as you continue to borrow the spell. Traditionally, most people do not trust users of Black Magic (those who draw on the powers of Yomi), but White Magi are still looked at with caution.