Blog topic #4 :What is usablility?

Usability is an approach to product development that incorporates direct user feedback throughout the development cycle in order to reduce costs and create products and tools that meet user needs.
There's something wrong with our computer systems. Much of our time is filled with frustration - websites and intranets that don't let us find the information we want, word processors that lose hours of work with a click of the mouse, remote controls that have more buttons than we could possibly need.
'Usability' is widely seen as the answer to many of these frustrating interactions with technology. There are usability books, websites, guidelines and checklists, so why are products and systems getting harder to use instead of easier?
'Usability' is an umbrella term that encompasses two related concepts:
1.Usability is an attribute of the quality of a system:
"We need to create a usable intranet"
2.Usability is a process or set of techniques used during a design and development project.

USABILITY TESTING:
Usability testing is a technique for ensuring that the intended users of a system can carry out the intended tasks efficiently, effectively and satisfactorily. Usability testing is a means for measuring how well people can use some human-made object (such as a web page, a computer interface, a document, or a device) for its intended purpose, i.e. usability testing measures the usability of the object. Usability testing focuses on a particular object or a small set of objects, whereas general human-computer interaction studies attempt to formulate universal principles.

A good design that had testing applied to it is even better, but more comments on this later. Usability testing tends see the trees instead of the forest. You tend to figure out "that button's label is confusing" not "movie and music players represent fundamenatlly different use cases". Because of this usability testing tends to get stuck on local maxima rather than moving toward global optimization. You get all the rough edges sanded, but the product is still not very good at the high level. A good designer will also predict and address a strong majority of "that button's label is confusing" type issues, so if you do perform usability testing you'll be starting with 3 problems to find instead of 30. That's especially important because a single usability test can only find several of the most serious issues: you can't find the smaller issues until the biggies can be fixed. In summary: with a designer you're a lot more likely to end up optimizing toward a global maximuum rather than a local maxima, AND if you do testing it will require far less usabilty testing to get the little kinks out.

Why is usability important to good design?Usability is important to web site design because if it's missing, the site can alientate or confuse the user, as well as detract from whatever your main message, product or service is.
Good design should be seamless, almost invisible.Good design isn't just about a web site looking cool, it's about helping the site communicate it's goal with as little effort as possible on the part of the user. If the site has strong usability, more people will notice how great the design is because they won't be wasting time trying to figure out how the site works.
some examples:
1.Adobe 2.Microsoft3.Dreamweaver MX 2004