Usability Implies Accessibility Implies Openness,
Three Goals, One Methodology
Everyone uses the web towards different goals. Companies often want to make money, using the medium to give their products and services more exposure or even to do business online. Individual users on the web often operate in an information or task oriented manner. Generally speaking they want to get information, share information, exchange information, accomplish some task, influence others to perform some task, or allow others to accomplish some task. Being effective on the web hinges greatly on communication. Failings in communication result in wasted effort, tarnished relationships, and poor results.
The level of success in communication has many factors. A great deal of success evolves haphazardly, but there are a large number of social sciences that can help improve results. Usability plays a big factor in how well a web site can be used by it's target audiences and relies heavily on Information Architecture and Ergonomics. Information Architecture is a complex field that touches on a lot of different disciplines to improve the overall effectiveness of a web site's ability to communicate. The quality, presentation, organization, and management of information in web site all influence its usability. Ergonomics is the study of how Human physiology and psychology limit and dictate practical designs. For something to be usable it must conform to certain human expectations that are inate or learned. Usability makes communication with web users easier and more effective.
Standards Based Design, especially of Open Standards, plays a critical factor in communication on the web. In order for the web to work there must be a critical mass of individuals that agree on some standards for information sharing. This creates an open exchange of information, Openness. Standards based design makes communication possible, without it the Internet and even computing wouldn't be where is is today.
Standards based design is also critical to Accessibility. Accessiblity, in the general sense, is a measure of how inclusive a design is with respect to the capabilities required for use. As something becomes more accessible, more people can use it. Accessibility most commoly is applied to accomidate people with disabilities, but it can also mean accomidations for those with specific technological limits, or even temporary environmental impairments. People with text-only devices or small screens are one example of a technological limit. An extreme example would be people with no computer of their own. These individual rely on print-outs and public access to computers, such as in a library. Examples of people with temporary impairments include those that are in a noisy area, or using a screen which is difficult to see because of glare.
There is a special relationship between usability, accessibility, and the use of open standards where the web is concerend. The very nature of the web creates a chain of implication that asserts, in general, that as a site becomes more usable is also becomes more accessible as a site becomes more accessible it provides content through more open standards. This chain of implication arises from the definitions of the web, web usability, web accessiblity, and open standards. It is note worthy because it leads to a methodology that affirms the evolution of the web and clearly shows why the web works. This unified methodology embraces and strengthens the case for usability, accessiblity, and open standards because it connects the three such that it can be asserted that if a web site is made more usable it is also being more accessible and the site is working more within open standards. If this is not the case then an underlying principle of the web had been violoated, and clearly something has been done wrong.
Definitions For the Purpose of This Methodology
Specificly, Web Documents
The term Web Page is often used interchangably with term HTML Page. This mistake can lead to many confusions and misconceptions. There is nothing about the Internet, the Web, or even HTTP that specificly restricts communication on the web to HTML. This would be annalogous to equating cars to automoblies. Even I am guilty of saying, "I drove my car today" when what I really meant was, "I drove my SUV today". There are a wide variety of documents that are transfered over the web. Most are used in conjunction with HTML, often displayed inline such as the case of images. PDF is however an example of a type of document that is perfectly valid to use on the web. PDFs can link to other PDFs, they can be made accessible, and with enough development they could be made a highly usable method of web communication. PDF, as a standard, is signifigantly less open than HTML.
A web document is a single unit of Web Communication. It is not the largest unit and it is not the smallest unit, but rather the net result of a single HTTP transaction. In a browser, typing a URL in the address bar, or clicking a link initiates an HTTP transaction2. This means every file that can be aquired on the web is a web document. Clearly some web documents, like images, are not intended to be used as stand alone entities. There is nothing saying that images cannot stand alone, but the current file formats lack the capability or standards to facilitate accessibility and openness. As a functional unit, images can have very high or low usability which can be different from their usability when presented inline within an HTML document. To make the distinction clear, interlinked self-sufficient documents are refered to as Web Document, or Independant Web Documents when the need for distinction exists. Documents that may not be able to stand on their own, such as images, are Dependant Web Documents.
To further complicate the definition of web documents, many sites now employ dymanic pages. These pages are documents generated on demand by a script on the server. Two users requesting the same dynamic page might to slightly or wildly different web documents. It is for this reason the distinction between a web page and a web document is made. In many cases the two are one in the same, but with the proliferation of dynamic pages it is important to understand that the file you see in the browser may be very different than the file on the server.
Usability is the measure of how effectively something can be used by it's target audience. Web Usability applies specificly to how effectively web documents can be used by the general public, meaning anyone. Clearly, perfect and universal usability is not possible, but there are many ways to approach near perfect usability. Usability implies Accessibility because users with limited capabilities (physically, mentally, and technologically) as part of the general public. As usability increases the audience becomes more inclusive. Usability also implies Openness because open standards are essential to promoting a more inclusive general public. This definition of Usability extends the traditional computer science definition. The traditional definition of Usability had the foresight to include "accessibility for users with disabilities", but not Accessibility in the modern sense.
Usability is about a user centric design process. The inherint opposite of this concept is the designer centric design, which this document will not explore. The designer centric design has been the norm throughout history and is an excellent experimental approach, but has been proven time and again to produce ineffective web sites3.
Accessibility is the measure of how well something can be used by anyone. Web Accessibility and Web Usability are very closely tied together because while traditional Usability was focuesed on a specific sub-set of the population, the web is designed for everyone. Traditionaly, Accessiblity has focused on designs that were inclusive of people with disabilities, but in the sense case of the web this sense of inclusivness has been extended to those who do not have as much access to technology as others. This underpriviledged group has long been underrepresented in Usability efforts. Accessibility implies Openness because access for users with disabilities rely on assitive technologies, and the underprivledged often rely on assistive services. Openness speeds the development of assistive technology and the increases the efficiency of assitive services.
When possible, Accessiblity is accomplished with minimal impact to desirable Specialization. Specialization is a feature of a web site that makes it a more powerful tool to a specific sub-set of the general public. Accessiblity can often be acheived with little or no impact to Specialization. Usability on the other hand often works directly against Specialization. Web Accessibility increases a user's ability to use a website despite their capabilities. Web Usability increases a user's ability to use a website despite their competency. This is the key distinction. Sites a that are targeted at a sub-set of the population because of competency (or the willingness to become competent) in a given field would desire Accessibility from an ethical standpoint, but can trade-off some Usability as a necessity. Thus Usability Implies Accessibility, but Accessibility does not necessarily imply Usability.
Openness is the measure of how simply something can be shared. Web Openness does not mean that information cannot be restricted to a sub-set of the population. Openness is essential to Accessiblity and Usability which both focus on more inclusive sets of the population, but the direction of implication ensures that Openness does not get in the way of implementing them in both public and private systems in very interwove ways. HTTPS is an excellent example of this employment of a public standard over a public medium that is secure, safe, and private. Open Standards that are new or implement restrictions may raise issues with Accessibility and Usability, but to a lesser extent than Closed alternatives. This Restrictive Openness may require extra steps to get through and thus decrease usability. Some users may lack the access to technology or assistive technology compatable with the newest Open Standards or Restrictive Open Standards, but support for these will be more widely available faster than Closed or Proprietary Standards.
Ultimately, Open Standards are what the Internet and the Web are built on. Close and Proprietary Standards are artificial constructs in this environment that have been created to protect fragile corporate egoes and pad corporate wallets. Closed Standards create a false sense of security and increase dependancy on a single vendor of tehcnology. This is not to say that Closed Standards cannot be Accessible or Usable, but the information inside these closed systems must be made open by the vendor or client and this is an extra step that must be paid for at the client's expense. There is a large and highly graded line of gray between Open and Closed Standards. Technololgies that are largely proprietary, but allow all or most information within them to be exported to Open Standards are much less problematic than technolgies that store information in Open formats, but prevent loss less export.
Practicality of a Unified Methodology
The power of implication is that is a brain dead assertion. Implication is a logistics term. If A implies B, B is always true when A is true. If you want A and B to both be true you only have to make sure A is true, B naturaly follows. The other nice feature of implication is that if we don't care about A, or have problems making A true, we can still make B true. When A implies B, B might be true or false even when A is false. Basicly, B is a freebie when all the work for A is done. A Unified Methodology means that If we strictly follow Web Usability methodology, we automaticly get Accessibility and Openness. This does not meant that no work is done to make a web site accessible or compliant with open standards. It does mean that this work would need to be done anyways to make the web site "usable". What makes the whole proposition tricky is that implications work great when only "true and false" are invovled, but in the real world Usability, Accessiblity, and Openness are continums. There is a certain satisfactory threshold for each objective, often this threshold is specific to a specific situation. While implications don't work with shades of gray specificly, it can be said that in general, as the level of usability goes up the level of accessibility will tend to go up and the same holds for accessiblity and openness.
If a developer makes one change to a website to make it more usable that may not have an impact on accessiblity or openness. In the long run, since web accessiblity is a sub-set of web usuability, if a number of changes are made to improve usability some of those will improve accessiblity directly or indirectly. If no improvement is made in web accessiblity there are a limited number of web usability improvements that can be made.
Similarly, web accessiblity relies on open standards. If web accessiblity is improved for a site there is more openness in the site, more open content. This does not imply that the use of closed standards is reduced, only that more conent is accessible through open standards reguardless of whither or not it is also available in closed standards.
Since these two implications are chained there is also the implication that as web usability increases, openness increases. This is the case because of the diverse nature of the internet. Putting a web site up in HTML, which is an open standard is much more usable than a web site made of interlinked Microsoft Word documents. Despite the high saturation of Microsoft Office in the business world,it is still a proprieary format and a number of users do not have access to software that can handle it. Make a site usable means providing content thought open standards. If everyone had access to software that could open this file format it would tend to imply that either a technological monopoly exististed, or despite being part of a prorietary tecnology the file format had been made open so that other software packages could use the file to facilitate interoperability. In the case of Microsoft Word documents, the files can be opened in a wide variety of software packages, but often lacking features of the full package. How important these features are to the effective communication and use of the document would directly impact how usable and accessible it is.
How useful this Unified Methodology is to a developer ultimately depends on the demands placed on them. Usability has a great deal of business rationale for it, many justify or more than justify the costs. Every commercial venture on the web should strive for usability strictly out of self interest. The only scenario where usability isn't imporant to the vendor would be a technological monopoly, where the user or customer has no other choice. Comercial ventures aside, usability makes communicaiton on the web more effective. Usability reduces frustrations and facilitates efficient work flow. Accessibility is mostly a legal and ethical concern, but there are business cases for it as well. The strongest and most universal arguments for accessibility are the ethical ones. When Usability is followed to the letter and sprit of the law, no seprate justification is even needed for accessibility. Openness is perhaps the most most altruistic goal among the three. There is not a strong business case for Openness that does not rely on long term outlook and a lot of unproven Open Source rhetoric. There is a strong business case for interoperability and Openness is a way to acheive interoperability with no or minimal investment in proprietary systems. For developers that desire Openness, this feature is icing on the cake. For others it is lard and sugar that can be ignored to an extent as long as they understand that depsite investment in proprietary and closed systems they must eventualy make any content they want to be usable or accessible open.
The Case for a Unified Methodology
The old saying, "Kill two birds with one stone" puzzles me. Whether this dates back to the nomadic hearders of pre-historic times, or something a little more modern along the lines of hunting for sport, I am unsure. What I do know is that killing two birds with one stone sounds like a tricky proposition. Either the stone is rather sizable and would utterly crush said birds, or it must be traveling at sufficient speed to impact two targets along the same vector. In the latter case I don't imagine there would be much left of one or either bird. The point I am trying to make is that to me, this saying connotates overkill more so than effeciency.
Morally ambigious objectives aside, meeting three objectvies with little or no additional work or duplicated effort is clearly a positive thing. The fact that Web Accessiblity is a subset of Web Usability can be taken in a positive or negative light. A common misconception is that there is no overlap between Usability and Accessiblity, that somehow Usability only applies to those without disabilities.
Were this the case, it might mean more work for the web developer if Accessiblity suddenly became important. Accessibility is an ethical concern, although for many web sites it is a worth while investment. Making commercial pages accessible makes sense from a purely economic stand point, people with disabilities are a viable demographic of the population. If two compedators provide an online service, but only one is accessible, that one compedator will get most it if not all of the business from users with disabilities and will most certianly have a higher customer satisfaction level among those users. Accessibility makes sense even for personal web sites. The whole point of putting up a web page, presumably, is to share information. If you desire to share a photo-journal on the web, and happen to have no friends or relatives that are disabled then accessibility may not be a concern. However, if by chance someone with a disability happens live in your area and stumbles upon your site because of some shared interest they may very well be blocked from getting to know you, thus an opportunity is missed. If you create an online forum, but the server side scripts genrate inaccessible code you will not likely hear the views and opinions of users that find themselves unable to use the site. An inaccessible online community, intentionally or not, breeds discrimination.
In reality, Accessibility is a requirement for Usability. Ignoreing accessibility while considering usability effectively asserts that no one in your intended audience is disabled. Usability is a self-serving methodology, following usability practices makes your pages "better" because they are easier to use. For businesses this means better sales and higher customer satifcation. For individuals, usability insures that if the content of a website is meaningful or useful to some group of users it is much more likely to be used, referenced, and linked to. Usable sites are more appealing to users, so usability is a key player in natural selection on the web. Accessiblity becomes the ethical easter egg, the surprise that just happens, when usability is done properly.
In the same manner, open standards are an added bonus for the usable site. Featuers such as RSS feeds, searchable content, and skinable pages can signifigantly enhance the appeal and usage of a website. These are all made easier when open standards are followed, many of these features signifigantly enhance usability. Clearly, this unified methodology is
Implications of a Unified Methodology
The Unified Methodology doesn't
Everyone Loves the Three for One Special
A popular buzz word this year is "Holy Grail". It is used a lot to describe an application, technology, or process that acheives a lofty goal. The usage is similar to "Killer App", but the words conjure a more majestic imagery. Also, a field can have more than one "Killer App" and the term is inherently specific to software, so "Holy Grail" tends to be favored by companies seeking to distinguish themselves1. Ultimately, the term "Holy Grail" implies an end-all be-all solution. Without getting into a lot of common practice bashing, I will just go so far as to say that it's absolutely absurd the way this particular buzz word is used. It's crass, irreverent, moronic, and down right lame as a marketing ploy. In reality, the "Holy Grail" would be the lofty goal itself. The Grail is an ends, not a means.
Openess is what makes the web so powerful. It is a public space. The same technology that puts web sites on the internet can also be used in intranets. There is nothing about the protocols and specifications that make up modern web technology that prevent information from being made private, secure, or confidential. The web also adapts, or rather, is adapted at a steady pace to meet new needs and expectations. This trait of the web is enhanced and limited by the community of users. Some technologies and sites on the web are more open than others. Open Standards Based Design is a subset of Standards Based Design that focuses on standards that are publicly available to learn, develop with, and use. Openess makes communication on the web inexpensive and flexible.
There is a lot of overlap between Usability, Accessiblity, and Openness on the web. Each is a methodology towards a goal. By making content accessible certain things are done that also improve the openness and more usablility inheriently means greater accessiblity and openness. Generalizations can make this argument invalid, so Usability, Accessibility and Openness must be very carefully defined.
1. And yes, I know it is oximoronic for a company to try and distinguish itself with buzz words, but they do it all the time.
3. Unless your goal is create a website for like minded designers and deveopers, in which case the results are mixed.