man security 

on FreeBSD

https://man.freebsd.org/cgi/man.cgi?query=security

One thing I appreciate in great documentation is when it includes a short “mental model” before diving into the API.

For example some projects start with: – what problem the tool solves – how the system is structured – the typical workflow

Once you understand that model, the actual reference docs become much easier to follow.

Without that context documentation often turns into a list of functions rather than something that teaches how to use the product.