A BDSM checklist is an exploration tool developed by BDSM practitioners to help them organize their kinks, fetishes and interested activities, as well as provide them with a negotiation tool for playing with others. It is often a long, extensive list of likes and dislikes, things to try and things to never ever do. Whether your checklist is long or short, it is not a measure of how kinky you are so start where you are and build from there.
BDSM checklists all live under different names. You can call them limit lists, negotiation lists, negotiation checklists and perhaps ones I've never heard. They are all based on a similar idea. If you make a list of the things you enjoy or don't enjoy you can easily share them with the person you want to play with to find out if you can build a scene that will satisfy both of your needs and desires.