Ignite
Ignite is an elemental Status Ailment associated with Fire that burns the affected target, causing Fire Damage over time.
Ignite is typically inflicted by Critical Strikes of Fire Damage. There are other ways for Ignite to be applied as well. Targets cursed with 
Flammability have a chance to be Ignited when hit with any Fire Damage. Skills such as 
Burning Arrow have a built-in chance to Ignite targets.
The base duration of Ignite is 4 seconds. The burning damage over time is a third of the initial hit of Fire Damage, per second. Therefore, over the base duration, the target will take 4/3 of the damage dealt by the original hit.
Separate applications of Ignite do not stack cumulatively. Each ignite effect remains present on the target until it runs its course, but only the one with the highest damage per second will cause damage at any given moment. For example, assume an enemy is inflicted with Ignite for 100 damage per second, then after 2 seconds it is inflicted with Ignite for 50 damage per second. The outcome will be 400 damage over 4 seconds followed by 100 damage over 2 seconds.