The magic of inscription essentially takes the powers of sorcery and makes them permanently present in the world. A practitioner of inscription, usually someone who is also a sorcerer, will use various runes, carvings, and magical circles especially to replace what would otherwise be done with magical words and gestures.
As long as a source of divine chaos is supplied and the physical components in the proper amount for a spell, a competent inscription can perform the same spell repeatedly. Because of this, inscriptions are usually created in three ways:
As a binding
As an enchantment
On a ley line
If an inscription is used to bind an entity with innate magic, then that entity's magic can be drawn into the inscription, making a self-sustaining spell. As long as the entity remains alive, they will supply the power for the spell. As such, bindings can be used to augment the powers of an innately magical being (the bows of the elves are famous for this), or they can be used more nefariously to forcibly bind a magical creature into place and use its power for some greater purpose.
An inscription used for an enchantment is one that is inert unless supplied with divine chaos. In the days of the Melokai, this was often used to create equipment that only a Melokai could use and sustain. However, there are some rare artifacts that are inscribed in a way so that they will recharge themselves, providing the power of a magical spell to anyway, and infinitely. Many mythical items of great power over the centuries have been of this sort.
Finally, inscriptions created on a ley line will last infinitely as long as they remain within a ley line. With chaos constantly funneling out of the ley line, the inscription is able to absorb it indefinitely and sustain a spell. Melokai laboratories and schools were often built on powerful ley lines for just this reason. Indeed, The College was reputed to have been built in the center of a massive ley line. Some very rare and powerful inscriptions can apparently bind themselves to a ley line even if they are removed, allowing them to draw its power even from a distance. However, this is apparently very dangerous, and can tear reality open, like pulling a thread from your clothing.