Cooking analogy: books about analysis/the history/etc of cooking
Understanding oriented. Not any practical value.
Could also be called "discussions". Designed to be read at your leisure, no code required.
Typically not explicitly created, but instead are interspersed in other documentation (this is not the ideal way). They can be hard to create!
Are these architecture decision records?
Provide context, discuss alternatives. Don't instruct (that's a how-to guide) or provide technical references (that's a reference).
You don't need to know about this, but it could be nice to understand!