User-Centered Systems Design: A Brief History - Foundations for Designing User-Centered Systems - page 48

the component parts of the system), as systems get larger it is important to develop
functional models that simulate what the component parts do themselves and in
interaction with each other.
(7) Utility/Usefulness is an important concept always to consider when
designing systems. Is it ultimately useful for users and how long is its likely
usefulness? Is this something that will become an everyday system or an infre-
quently used system? When it is used, how useful do users find it or are there other
workaround that users would rather engage with? Usefulness can be measured
both in terms of how often and in what way something is used, but can also be
measured with subjective scales like 'how much do you like this?' People may find
something useful because it makes them feel good about themselves rather than
because it is an efficient, reliable system with a highly usable interface from our
perspective as designers.

2.4 Summary

In this chapter we have provided an overview of research areas that have con-
tributed to our understanding of user-centered design. User-centered design draws
on multiple sources of knowledge to support creating systems that are based on
users' abilities, capabilities, and task. What all these approaches have in common
is the perspective that when designing we need to consider variation and similarity
in the contexts, people, and tasks that characterize different design situations and
settings. A one-size-fits-all approach seldom works to achieve the most productive,
safe, and enjoyable design solution. We summarize this perspective by inviting
you to remember that design is about considering particular people doing par-
ticular tasks in a particular context—our focus in this topic is people doing tasks
using technologies, but this perspective can be more generally applied.
It is worth highlighting at this point that, in order to comply with ISO standard
9241-210 (which now refers to Human-Centered Design, rather than User-Cen-
tered), the following four activities are now requirements (previously they were
recommendations):

1. Understanding and specifying the context of use (including users, tasks,

environments)
2. Specifying the user requirements in sufficient detail to drive the design
3. Producing design solutions that meet these requirements
4. Conducting user-centered evaluations of these design solutions and modifying
the design to take into account the results.

Our aim in this topic is to provide you with the foundations that will help you to
meet these requirements. In the first part of the topic we focus on the capabilities of
users. We categorize these capabilities into anthropometric, behavioral, cognitive,
and

social aspects. Although we separate issues into these categories, we