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The aim of this lecture is to understand the strategic nature of usability

. The aim of this lecture is to understand the nature of the Web

35.1 The relationship between evaluation and usability?

With the help of evaluation we can uncover problems in the interface that will help to
improve the usability of the product.
Questions to ask

. Do you understand the users?

. Do you understand the medium?

. Do you understand the technologies?

. Do you have commitment?

. You must understand the constraints of technology

. What can we implement using current technologies

. Building a good system requires a good understanding of technology
constraints and potentials

. Do you know your users?

. What are their goals and behaviors?

. How can they be satisfied?

. Use goals and personas

. Building usable systems requires commitment?

. Do you have commitment at every level in your organization?

. You must understand the medium that you are working in to build a good
usable system

Nature of the Web Medium
The World Wide Web is a combination of many different mediums of
It would be true to say that the Web is in fact a super medium which incorporates all
of the above media.
Today’s we pages and applications incorporate elements of the following media:

. Print

. Video

. Audio

. Software applications
Because of its very diverse nature, the Web is a unique medium and presents many
challenges for its designers.
We can more clearly understand the nature of the Web by looking at a conceptual
Print (newspapers,
magazines, books)

Video (TV, movies)

Audio (radio, CDs,
Traditional software

The Surface Plane
On the surface you see a series of Web pages, made up of images and text. Some of
these images are things you can click on, performing some sort of function such as
taking you to a shopping cart. Some of these images are just illustrations, such as a
photograph of a book cover or the logo of the site itself.
The Skeleton Plane
Beneath that surface is the skeleton of the site: the placement of buttons, tabs, photos,
and blocks of text. The skeleton is designed to optimize the arrangement of these
elements for maximum effect and efficiency-so that you remember the logo and can
find that shopping cart button when you need it.
The Structure Plane
The skeleton is a concrete expression of the more abstract structure of the site. The
skeleton might define the placement of the interface elements on our checkout page;
the structure would define how users got to that page and where they could go when
they were finished there. The skeleton might define the arrangement of navigational
items allowing the users to browse categories of books; the structure would define
what those categories actually were.
The Scope Plane
The structure defines the way in which the various features and functions of the site
fit together. Just what those features and functions are constitutes the scope of the site.
Some sites that sell books offer a feature that enables users to save previously used
addresses so they can be used again. The question of whether that feature-or any
feature-is included on a site is a question of scope.

The Strategy Plane
The scope is fundamentally determined by the strategy of the site. This strategy
incorporates not only what the people running the site want to get out of it but what
the users want to get out of the site as well. In the case of our bookstore example,
some of the strategic objectives are pretty obvious: Users want to buy books, and we
want to sell them. Other objectives might not be so easy to articulate.
Building from Bottom to Top
These five planes-strategy, scope, structure, skeleton, and surface¬provide a
conceptual framework for talking about user experience problems and the tools we
use to solve them.
To further complicate matters, people will use the same terms in dif¬ferent ways. One
person might use "information design" to refer to what another knows as "information
architecture." And what's the difference between "interface design" and "interaction
design?" Is there one?
Fortunately, the field of user experience seems to be moving out of this Babel-like
state. Consistency is gradually creeping into our dis¬cussions of these issues. To
understand the terms themselves, how ever, we should look at where they came from.
When the Web started, it was just about hypertext. People could create documents,
and they could link them to other documents. Tim Berners-Lee, the inventor of the
Web, created it as a way for researchers in the high-energy physics community, who
were spread out all over the world, to share and refer to each other's findings. He
knew the Web had the potential to be much more than that, but few others really
understood how great its potential was.
People originally seized on the Web as a new publishing medium, but as technology
advanced and new features were added to Web browsers and Web servers alike, the
Web took on new capabilities. After the Web began to catch on in the larger Internet
community, it developed a more complex and robust feature set that would enable
Web sites not only to distribute information but to collect and manipulate it as well.
With this, the Web became more interactive, responding to the input of users in ways
that were very much like traditional desktop applications.
With the advent of commercial interests on the Web, this application functionality
found a wide range of uses, such as electronic commerce, community forums, and
online banking, among others. Meanwhile, the Web continued to flourish as a
publishing medium, with countless newspaper and magazine sites augmenting the
wave of Web-only "e-zines" being published. Technology continued to advance on
both fronts as all kinds of sites made the transition from static collections of
information that changed infrequently to dynamic, database-driven sites that were
constantly evolving.
When the Web user experience community started to form, its members spoke two
different languages. One group saw every problem as an application design problem,
and applied problem-solving approaches from the traditional desktop and mainframe
software worlds. (These, in turn, were rooted in common practices applied to creating
all kinds of products, from cars to running shoes.) The other group saw the Web in
terms of information distribution and retrieval, and applied problem-solving
approaches from the traditional worlds of publishing, media, and information science.

This became quite a stumbling block. Very little progress could be made when the
community could not even agree on basic terminology. The waters were further
muddied by the fact that many Web sites could not be neatly categorized as either
applications or hypertext information spaces-a huge number seemed to be a sort of
hybrid, incorporating qualities from each world.
To address this basic duality in the nature of the Web, let's split our five planes down
the middle. On the left, we'll put those elements specific to using the Web as a
software interface. On the right, we'll put the elements specific to hypertext
information spaces.
On the software side, we are mainly concerned with tasks-the steps involved in a
process and how people think about completing them. Here, we consider the site as a
tool or set of tools that the user employs to accomplish one or more tasks. On the
hypertext side, our concern is information-what information the site offers and what it
means to our users. Hypertext is about creating an information space that users can
move through.
The Elements of User Experience
Now we can map that whole confusing array of terms into the model. By breaking
each plane down into its component elements, we'll be able to take a closer look at
how all the pieces fit together to create the whole user experience.
The Strategy Plane
The same strategic concerns come into play for both software products and
information spaces. User needs are the goals for the site that come from outside our
organization-specifically from the people who will use our site. We must understand
what our audience wants from us and how that fits in with other goals it has.
Balanced against user needs are our own objectives for the site. These site objectives
can be business goals ("Make $1 million in sales over the Web this year") or other
kinds of goals ("Inform voters about the candidates in the next election").
The Scope Plane
On the software side, the strategy is translated into scope through the creation of
functional specifications: a detailed description of the "feature set" of the product. On
the information space side, scope takes the form of content requirements: a
description of the various content elements that will be required.
The Structure Plane
The scope is given structure on the software side through interaction design, in which
we define how the system behaves in response to the user. For information spaces, the
structure is the information architecture: the arrangement of content elements within
the information space.
The Skeleton Plane
The skeleton plane breaks down into three components. On both sides, we must
address information design: the presentation of information in a way that facilitates
understanding. For software products, the skeleton also includes interface design, or
arranging interface elements to enable users to interact with the functionality of the
system. The interface for an information space is its navigation design: the set of
screen elements that allow the user to move through the information architecture.
The Surface Plane
Finally, we have the surface. Regardless of whether we are dealing with a software
product or an information space, our concern here is the same: the visual design, or
the look of the finished product.

Using the Elements
Few sites fall exclusively on one side of this model or the other. Within each plane,
the elements must work together to accomplish that plane's goals. For example,
information design, navigation design, and interface design jointly define the skeleton
of a site. The effects of decisions you make about one element from all other elements
on the plane is very difficult. All the elements on every plane have a common
Function-in this example, defining the site's skeleton-even if they perform that
function in different ways.elements on the plane is very difficult. All the elements on
every plane have a common function-in this example, defining the site's skeleton-even
if they perform that function in different ways.
This model, divided up into neat boxes and planes, is a convenient way to think about
user experience problems. In reality, however, the lines between these areas are not so
clearly drawn. Frequently, it can be difficult to identify whether a particular user
experience problem is best solved through attention to one element instead of another.
Can a change to the visual design do the trick, or will the underlying navigation
design have to be reworked? Some problems require attention in several areas at once,
and some seem to straddle the borders identified in this model.
The way organizations often delegate responsibility for user experience issues only
complicates matters further. In some organizations, you will encounter people with
job titles like information architect or interface designer. Don't be confused by this.
These people generally have expertise spanning many of the elements of user
experience, not just the specialty indicated by their title. It's not necessary for thinking
about each of these issues.
A couple of additional factors go into shaping the final user experience that you won't
find covered in detail here. The first of these is content. The old saying (well, old in
Web years) is that "content is king" on the Web. This is absolutely true-the single
most important thing most Web sites can offer to their users is content that those users
will find valuable.

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