The public mental model is simple on purpose: work / notes / experiments.
Work: things that take craft, execution, engineering, design, or sustained effort.
Notes: things I am learning or trying to understand.
Experiments: things I am trying without requiring certainty or success. Prototypes, failed approaches, unusual interfaces, hypotheses. Successful and failed experiments are equally valid archive entries.
No taxonomy needs to be perfect. The goal is navigability, not bureaucracy. Over time the archive should become a graph — an experiment that became a note, a build log that became a project, an essay that changed because the project did.