Very briefly, plot means what happens in a story. To be more precise, it means an incident or a series of events leading to important consequences. Plot is simply cause and effect played out on your page.
Think of throwing a pebble into a pond. It is a small action but one that leads to big consequences. Plot is what people (your characters) say, do and feel that makes a difference to what happens next.
Let’s create an example: in a moment of mild intoxication Marla tells her best friend, Jodie, that she once had an affair with Paul, a neighbour. The action of telling her secret sets off a chain of consequences. The ripples of that particular pebble will reverberate in the lives of all the characters.
Thought and emotion can also set off consequences but only once they are acted upon. Jodie can be angry with Marla for betraying her husband but that’s not plot until Jodie acts on it. Thinking about or feeling some emotion isn’t plot. But emotions are a very good way to start an action that leads to further consequences and thus to a satisfying story.
Also, what isn’t plot: this happened and then that happened and then this happened and then that happened. It’s not even a story because there are no consequences. Something must be at stake and in all the ‘happenings’ there must be something important enough to bear the weight of consequent ‘happenings’.
A man dies. That is not a plot. A man dies and his wife dies. Again not much of a plot. A man dies and his wife commits suicide. We’re getting somewhere; that is the beginning of a plot. A man dies, his wife commits suicide and her daughter starts to ask why her father died and why her mother was so frantic that she kills herself. A plot! The father’s death is the event that has significant consequences. If the daughter merely felt sad there would be no story.
All plots emerge from that one moment when something happens that is significant enough to start off a chain of consequences.
I’m trying to imagine how I would put those words of wisdom to good use in my present project. My next Nana Naills story is a crime novel (working title: Nana and the Nest of Vipers). So the plot hinges on the finding of a dead body – as you do in a crime story. That’s my pebble. Ah! Now I see. Each incident has consequences for the suspects. Hmm. I think I could work with that.