Knowledge Magic is one of the three branches of magic.
Knowledge magic differs leyline magic in that the source of energy is the information about how the spell itself works, rather than the energy of surrounding sentimentality.
Knowledge magic also differs from will magic in that the source of energy is not required to be inner power at the moment a spell is activated.
Knowledge magic is most useful for casting magic in areas with no leylines. The Great Blind Desert is an example of such a place, as it has the lowest density of leylines of any area on Mersia. Will magic is usable in such areas, but without a way to replenish one's internal reserves, it isn't sustainable.
Knowledge magic may also be used to improve one's efficiency with certain types of magic. In essence, the more familiar you are with the magic you're casting, the more efficiently such magic will use your potentia.