A word is nothing but a painting of a fire. A name is the fire itself.
Naming is the art of determining the true essence of a thing, not having mastery over it . Naming cannot be done by a normal human mind; it can only be done through the Sleeping Mind, which Elodin says humans use every day for reflexes such as catching . Traditionally, arcanists at the University studied naming ; however nowadays it is extremely rare for people to know more than one or two names.
Common names are names of simple materials, such as stone (Fela), wind (Kvothe), iron (Devan Lochees and Inyssa). However, even these names are extremely potent and extremely difficult to call: the name of the wind can stop the wind or start a thunderstorm . And to even call the name of stone, the arcanist needs to know everything possible about how the world can affect it: "how the light reflects from it, how the wind cups it as it moves through the air, how the traces of its iron will feel the calling of a loden-stone" .
Names of Sentient Beings
The name of a person is much more difficult to call because people shape their names by simply being alive.