98.12.01 ( d2
To Ted Nelson Home
To "Information Media" main page
To "Cinema of the Mind" main page
"Access structire" is a simple model of convenience and availability
I have been using since 1960 or 1961. But others have discovered
the same model since, and I do not know whether I am entitled to get credit
for first publication.*
* I submitted a column on it to ROM magazine about 1978,
but do not know whether my piece was published.
Something is at zero-order access if it is in use. This ordinarily
means in your hand, but that can vary.
at Zero-order access
(Note that an object may be in use even if you are
just holding it. For instance, a pen. Or a gun.) Gun
at Zero-order access
THE MAPPING OF ACCESS STRUCTURE
Something is at first-order access if one operation is required to
bring it to zero-order access.
Something is at second-order access if one operation is required to
bring it to first-order access.
Third-order (etc.) access.
Successive steps, or uncovering operations, are needed to bring the
object to lower orders of access.
When you go from one room to another, everything in the new room goes
to a lower level of access, and everything in the previous room goes to
a higher level of access.
A MODEL OF EVERYTHING
In other words, particular operations (especially moving around, turning
things on and off, opening boxes and closing them) affect whole groups
It is therefore possible to make maps of what operations bring some
objects closer, others farther away.
Everything has an access structure.
NOT TOO EXACT
This applies to equipment. It applies to information. It
applies to work in progress. It applies to friends. It applies
to parts of your body.
It applies to information. It applies to software.
But people do not consider access structure as an abstract property.
When we speak of "convenience" or "storage", we speak as if these were
global, uncalibrated qualities, rather than variables which we may choose
What constitutes an "operation" is not very exact; to a certain extent
it's a psychological issue, showing the number of steps a person thinks
are required. Still, it's clear and leads to some very clear mappings.
APPLICATIONS TO SOFTWARE
A menu, and the states of a program, may be considered as an access
map. And we may and should design such an access structure deliberately,
rather than juar letting it evolve as menus accrete into clumsier and clumsier