Plotters are those who rigorously outline their novel/other writing project and know exactly where it’s going to go before they even begin writing.
Pantsers go by the “seat of their pants”. They barely, if at all, plot out a novel before they begin. They discover the plot as they go along.
Plantsers are a mix of the two, and a very nice portmanteau to boot.
Now that you’re caught up, I thought of this analogy the other day. I have one foot in each of: (a) creative writing (b) hard science. Those can be difficult to combine for career mapping, but they’re great for thinking outside the box.
Here’s the analogy that helped me understand the differences between plotting, pantsing and plantsing.
Plotters are engineers. Engineers start with a design brief that details exactly what they are going to do. Generally, engineers are very concerned with keeping things cost-effective, light, aesthetically pleasing, etc. They can’t just go in blindly. The purpose of engineering is to design and construct something, and so they need to know exactly what they’re going to construct. Sure, after the product is made and tested they can change facets of it – even plotters need to revise their first drafts, after all – but it is all meticulously planned. Engineering is far more concrete, whereas science can be more up-in-the-air.
Pantsers are scientists. This analogy isn’t perfect, of course; especially with trying to appease grant boards, to get a project funded, to do something scientifically interesting, there has to be some planning. Pantsers don’t go in completely blind, either – they do some research (corresponding to reading background research in scientific journals, gathering experimental protocols) but they may not know exactly where it will fit into their overall story. Particularly in pure science, the idea is to explore and make observations as you go along. You shouldn't know what will happen, otherwise what's the point of observing?
Plantsers are mathematicians. Mathematicians, when trying to prove something or solve a problem, start with a number of assumptions, or axioms. These are analogous to a writer’s broad plot points. They know they cannot go outside these lines. But within that framework, they are free to “pants” it, to explore and try different methods for getting to their destination.
*My knowledge of the engineering, mathematical and possibly scientific methods may be faulty or overoptimistic, but this analogy helped me understand and might do the same for you.