Recording how things work.
WHY IT MATTERS
Knowledge held by one person is a risk, and answering the same question repeatedly is waste.
WHAT TO DOCUMENT
How things are done Why decisions were made What to do when something goes wrong Who is responsible for what
WHY THE REASONS MATTER MOST
They let future readers apply judgement rather than following blindly.
WHAT TO WRITE FIRST
Whatever you are asked about most.
WHY
It is proven to be needed.
WHAT MAKES DOCUMENTATION DECAY
Nobody owning it No update when things change Being written in bulk once
WHAT PREVENTS IT
Writing small pieces as you go Updating as part of making changes
WHAT TO INCLUDE IN EVERY DOCUMENT
What it covers When it was last reviewed Who owns it
WHY THE DATE
Readers must judge whether to trust it.
WHAT TO DO WITH OUT-OF-DATE MATERIAL
Fix it or remove it.
WHY REMOVING IS ACCEPTABLE
Wrong documentation is worse than none.
WHERE TO KEEP IT
Somewhere searchable, that people actually use.
WHAT KILLS ADOPTION
Documentation in several places Requiring special access Difficult to edit
WHAT TO MEASURE
Questions asked that documentation should have answered.
WHAT THAT LIST BECOMES
What to write next.
