The document discusses the importance of usability in web design. It defines usability as the extent to which a product is effective, efficient, and satisfying to use for its intended users. The goal of usability testing is to better understand how real users interact with a product and improve it based on those results. Usability principles include keeping the user informed, using familiar language, preventing errors, making objects and actions visible, and providing help and documentation.

1. USABILITY
Lecture 05

2. On web usability is necessary condition for
survival

3. Why Usability?

4.  It just make a sense
 I don’t need to read the manual
 A joy to use
 Everything is where I expect it to be

5. Usability is the science of making
technology work for people

6. According to ISO;
“The extend to which a specific product
used by specified user to achieve a
specified goal effectively, efficiently and
with satisfaction in specified context of
use”.

8.  The goal is to better understand how real
users interact with your product and to
improve the product based on the results.
 The primary purpose of a usability test is to
improve a design.
 In a typical usability test, real users try to
accomplish typical goals, or tasks, with a
product under controlled conditions.

10. .
Always keep the user informed about what is going
on. Provide appropriate feedback within a reasonable
time.

12. .
Speak the user’s language, with words and phrases
and concept familiar to user rather than system
oriented language.

13. .
Provide the clearly marked out to leave the
unwanted state without having to go through an
extended dialogue. Support undo, redo

15. Users should not have to wonder whether
different words, situations, or actions mean
the same thing.

17. Even better than good error messages is a careful
design which prevents a problem from occurring
in the first place.
5. Error Prevention

19.  Make objects, actions, and options visible.
 User should not have to remember information from one part of the
dialogue to another.
 Instructions for use of the system should be visible or easily
retrievable whenever appropriate.
6. Recognition Rather than Call

20. Accelerators -- unseen by the novice user --
may often speed up the interaction for the
expert user so that the system can cater to
both inexperienced and experienced users.
Allow users to tailor frequent actions.
7. Flexibility and Efficiency of Use

22. Dialogues should not contain information which is irrelevant or
rarely needed.
Every extra unit of information in a dialogue competes with the
relevant units of information and diminishes their relative
visibility.
8. Aesthetic and minimalist Design

24. Expressed in plain language (no codes)
Precisely indicate the problem
Constructively suggest a solution.
9. Help users Recognize, Diagnose
and Recover from Errors

28. Even though it is better if the system can be used without
documentation, it may be necessary to provide help and
documentation.
Help information should be easy to search, focused on the
user's task, list concrete steps to be carried out, and not be too
large.
10. Help and Documentation