We’ve seen non-linear storytelling sometimes without knowing it. This article does a great job explaining what linear stories are:

In a linear narrative structure, the viewer finds it facile to comprehend the way the narrative is moving. This is mostly because the viewer is naturally fed with all the information required to process whatever is happening on screen.

And then explaining what non-linear stories do:

However in a non-linear narrative structure, the viewer has to use his head in order to connect the dots. Non linear narrative structures are usually adopted to build suspense, to create tension or generally to create a sense of mystery within the spectator. The most crucial aspect of a non-linear narrative structure is that the narrative does not adhere to the norms of a generalized method of storytelling. In other words, in a non-linear narrative structure, there is no hard and fast rule to strictly follow a chronology.

Some types of non-linear narratives:

• Analepsis or a flashback – used to establish critical backstory, probably only used once or twice.
• Zigzag – alternating between two different timelines, often for the compare/contrast (like The Godfather II) and sometimes to provide answers in one narrative with the exposition of another (like in Memento)
• Prolepsis – or a flash forward, showing things that will happen in the future
• Syllepsis – or grouping multiple characters or stories to tell parallel stories that eventually interconnect (think Love Actually) or have some adjacent ideas or characters
• Retrograde – chronological storytelling in reverse chronological order – Mulholland Drive is an example, as is one story of The Last Five Years
• Achrony – disconnected, disjointed, disorganized (like Inception) with no real connection between the order in which events occur and the order in which they’re told
• Chronicle – events occur simultaneously but are told in no specific order (like Pulp Fiction) popular in disaster movies

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