These are two terms I was not familiar with until I joined the Bookstagram community. A plotter is someone who meticulously plans their story before they start writing and depending on who you ask, that's what they stick to when they write. A pantser is someone who just writes and see where they end up. ie: "Flies by the seat of their pants." A lot of the time, the ending of their own book is a surprise for them too as they just write and see where their characters take them.
I'm somewhere in between the middle of these approaches.
I like to know if there is enough of a story in my head to write, before I commit to a full series, which is usually three books for me. This strategy has served me well so far, and it's one I intend to keep. Its important to note that while I outline, I very rarely stick to it. This is where my characters take over, and it's one of my favourite parts of my writing process. I've spoken about it before how The Rule of the Damned had a very different ending to what I had planned, and I have zero regrets about it. Its a tactic I'm using for a potential new series I'm going to write too, and why I'm almost ready to announce it.
I've come across some authors that struggle with writers block or inspiration because they want to be either or of these writer types, and the point of this post is sharing that you don't have to be either. Embrace the parts of something that suit you, until it becomes something uniquely yours. You may be surprised what you discover when you do.