Stormlight

Stormlight is a radiant energy given off by highstorms that can be stored in gemstones and then laterused by Surgebinders. Stormlight is a source of light and power and is used to power the technology of Roshar. Stormlight also has the power to heal, though Stormlight healing is far from instantaneous.

Containing Stormlight
Gemstones are much better at holding Stormlight than other objects because the light can remain within them for weeks. Usually, those gemstones kept in spheres (the currency on Roshar), can be infused with Stormlight by leaving them outside during a highstorm. Infused spheres can also be obtained from money exchangers. Stormlight leaks quickly when held by a Surgebinder or infused into an object other than a gemstone, though persons can slow the leakage by holding their breath (which they can do for an extended time while holding the light). It is theorized that Voidbringers can hold Stormlight perfectly.

Surgebinding
Surgebinding refers to a group of ten magic systems that stem from Honor and Cultivation, two of the three Shards of Adonalsium present on Roshar. Each of Surgebinding's ten systems revolves around 'binding' two natural 'Surges,' for instance Gravity and Adhesion, to the Surgebinder's will. Surgebinding is powered by Stormlight, and the ability is granted to humans through bonding with a Spren, a type of elemental spirit native to Roshar. There are ten surgebinding branches.

Each Order of the Knights Radiance are divided up by what kind of Surgebinding the person uses. For example Windrunners use both Adhesion and Gravitation, and Lightweavers use both Illumination and Transformation.

There are 10 different Orders each with there own Ordeals which go hand-in-hand with there Surgebinding abilities. See the Orders of the Knight Radiance page for a more detailed explanation for each Order.