Runes are modifier items that can have various effects on the item they are applied to.

Rune of Shattering: Destroys an item, creating Shards from its affixes. The number of Shards created is random for each affix, equal to the tier of the affix at maximum and 1 at minimum.

Rune of Refinement: Rerolls the values for each affix but does not change their tiers. Each affix is rolled individually, so some may have better values than others.

Rune of Removal: Removes a random affix on an item, returning a number of shards equal to its tier.

Rune of Discovery: Adds random tier 1 affixes to all empty affix slots on an item. Has an increased chance of rolling rarer affixes. Does not cost Forging Potential, but cannot be applied to items with zero Forging Potential.

Rune of Shaping: Rerolls all of the implicits on an item.

Rune of Ascendance: Changes the item into a unique or set item of the same item type. Using this on a Silver Ring could turn it into any unique ring, including ones that are not Silver Rings. However, the Silver Ring cannot be turned into a Helmet. None of the other properties of the base item are retained. Rune of Ascendance cannot create unique or set items that are exclusive drops. There are many unique and set items that are only obtainable from bosses, for example.

Rune of Creation: Duplicates the item, but reduces the Forging Potential of both the original and the copy to 0.

Rune of Havoc: Shuffles the tiers of the non-sealed affixes on an exalted item with 4 non-sealed affixes. For example, an item with tier 2 strength, tier 7 dexterity, tier 3 health and tier 2 endurance might be changed to have tier 7 strength, tier 3 dexterity, tier 2 health, and tier 2 endurance.

Rune of Redemption: Randomly changes the exalted affixes on an item into different affixes. Does not change the tiers of the affixes or the rolls within the tiers.

Rune of Weaving: Uses a random amount of the remaining Weaver's Will or Weaver's Touch on an item to add or improve affixes as if you had slain many enemies with the item equipped.

Rune of Evolution: Evolves an exalted item into a Primordial exalted item, upgrading a random tier 7 affix on the item into a tier 8 affix, massively increasing the affix’s power and moving it to its own second sealed affix slot.

Rune of Corruption: Corrupts an item, changing it unpredictably and preventing you from being able to do any further crafting on it. The item may no longer be usable after it is corrupted. Removes all Forging Potential, Weaver's Will, and Weaver's Touch.

Glyphs are support items that can be used alongside Runes or Shards to affect the outcome of crafting.

Glyph of Hope: Modifies the outcome of a craft, granting it a 25% chance to have no Forging Potential cost.

Glyph of Chaos: Modifies the outcome of a craft when upgrading an affix. Randomly changes the upgraded affix to a different one that can spawn on that item type. It cannot change a prefix into a suffix or vice versa.

For example, if you use a fire resistance shard to a raise the tier of a fire resistance suffix the tier would increase as normal and then it would change into a different affix such as cold resistance or increased health.

Glyph of Order: Modifies the outcome of a craft when upgrading an affix. Prevents the roll of an affix within its range changing when it is upgraded.

Glyph of Despair: Has a chance to seal an affix instead of upgrading it. The sealed affix is moved to its own slot, leaving its old slot open for you to add a new affix. The sealed affix cannot be modified further and an item can only have one sealed affix. The chance to seal is higher when crafting on affixes of lower tiers, and is also higher for exalted items and items with more affixes.

Glyph of Envy: Changes the item’s subtype to a different one with the same class requirement when adding or upgrading an affix.

You can view how many Runes and Glyphs you have in the Crafting window or the Crafting Crafting Materials panel by clicking the button in your inventory.