Conflict, especially layered conflict, is the driving force behind every story. It supports narrative cause and effect and provides fuel for the tale. Conflict arises from forces that oppose each other and operates on multiple levels. Here are three types of conflict: external, internal, and mixed.
External conflict is typically represented through protagonist/antagonist interaction, but it can also take the form of environmental opposition such as a threat presented by a volcano, or a cyclone.
Internal conflict pits the protagonist against himself, in effect, turning him into the story’s antagonist — as in Fight Club where the conflict is between the character’s wishes, goals and desires, and between defining traits).
Mixed conflict is the most common form. Here the protagonist is confronted by a mixture of inner and outer obstacles.
One of my favourite films, The Matrix, is a great example of how conflict plays out across the layers. At an internal level, the protagonist, Neo experiences conflict between his belief that his current existence is real, and his growing conviction that the world as he knows it is an illusion. It is only when he comes to accept that he is The One that he is able to resolve his inner conflict and defeat the antagonist, agent Smith, and the machines, which have enslaved humanity. Neo’s struggle to attain the story goal, then, is pitted against a multilayered conflict.
Summary
Layered conflict is the fuel that powers your story. The layers can be described as external, internal, and mixed.