The original note, as written at the time
This is especially useful when you have to restart your computer in the middle of a workflow. You can capture the state of your computer before restart — this could entail open windows, their locations etc. When you restart, the computer can reopen these windows for you, placing them in the places where they were before the restart.
Ongoing development
Capture the state of a computer before a restart — the open windows, their locations, what was in them — so that after the restart everything reopens where it was.
The reason this matters is not convenience. It is that a restart in the middle of a workflow destroys a mental state that took an hour to build, and the machine has no concept of that loss.
Window positions look trivial and they are not. A person who works with six windows has arranged them into a diagram of the task: the reference on the left, the draft in the middle, the source on the right. Restoring the applications but not the arrangement restores the tools and loses the diagram.
The hard part is that some state cannot be restored, because it lives in the application rather than in the window. A half-written email, an unsaved sketch, a scroll position inside a document. The honest version saves what it can and says what it could not, rather than pretending the desk is as it was.
The design should be a snapshot rather than a rule — a named session you can return to, the way a browser keeps tabs, but for the whole desk and including the geometry.
And it should survive the crash, not only the orderly restart. A machine that only remembers its state when you ask it nicely is a machine that forgets exactly when you needed it.
The desk is a diagram. Put it back the way it was.