I've been noticing more and more Ajax powered pages where at the end
of the normal page end a call is made to fetch more content and is
added to the bottom of the page, in essence making the page longer on
the fly. A good example of this is on http://www.haystack.com
Twitter and Facebook do something similar but a button or link is
needed to expand the content.
I can a usability issue with clicking on a link and then having the
back button not return you to the same 'long' page you left from.
OK - so we work in the world of digital. Here the affordance is a
perceived one. But what about our real lives?
Here's the thing - I want to start a list of unusable real life
1. Elevator buttons: when I press the wrong floor (which is quite the
frequent occasion in my uncaffienated state before 12pm) why can't I
"unpress" my mistake?
2. Toilet doors: why does one open in and the next out. Furthermore -
why wash your hands when you must touch germ-ridden door handles after
the fact? If there is ever a need to have automatic doors - here it
In the discipline of IxD, the word has been used to define a possible
action perceived by a user within some environment (Norman 1988). In the
classic example, the affordance of a door with a flat metal plate is
"push." The affordance resolves to a verb, an action to be performed.
However, of late, I've seen the word used loosely to describe the clues
that suggest an object's possible actions.