Pattern recognition - a key to accessibility

The recognition of patterns seems to be trivial, in Reality it is a key to accessibility. It is one of the skills, in which creatures are much better than computers. For example, digital systems can recognize faces of persons in a photo, if they have templates; this is mainstream technology and is implemented in Facebook and some photo editing software. Cams are although capable to recognize and focus on faces. But till now, computers are not able to recognize certain faces out of a stream of persons like in main stations or air ports. There are too many parameters which they can not process, especially not so fast like humans or animals.

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The Importance of Patterns

In the usability, patterns are very important. Many persons are angry with Microsoft, Apple or Linux developers, when they change important elements in the user interface. You can assume that these big software producers are not changing such interfaces without many tests. Many changes are supposed to new computer users, which do not have much experience and so have other needs than skilled users. Skilled users are often working such a long time with a special system, that even small changes are breaking their working flow.

Let's take for example the start button in Windows. It was abolished in Windows 8. The differences were very small, but even experienced users think that the low success of Windows 8 is a result of the missing start button. Another example is the flat design in iOS 7. Apple is in fact a very conservative organization, for many years they didn't change the look and feel of iOS. In the introduction phase, many users refused the flat Design, some do till now.

Many persons miss an intersystem design language. Today, we are working with a lot of interfaces: Personal Computers, smartphones, TVs, automats and some more. Every system seems to have its own design philosophy and common rules in this area would reduce the stress and the count of input mistakes for many users. This would although improve the acceptance of this systems in the population.

Patterns for blind persons

When you hear patterns you perhaps think of puzzles and other visual patterns. But here are although patterns for blind persons, too.

For example, blind persons know that websites and other user interfaces are build on certain schemes. On the typical website, you find the header, a sidebar, the content and the footer. If you reach the first sidebar, you think that the content column will come next. If instead the sidebar is followed by the footer, you wonder what is happening. In fact, there are some sites where the content is behind the footer.

A typical pattern is the Send-Button on the end of a Form. It's clear: You get the steps in right order, first you will in your staff, than you send the results. In some cases there first comes a "Clear-Button" to clear the fields. The Clear-Button is not a quite good idea and seems to be the origin of many mistakes. But if you use it nevertheless, it should be behind the Send-Button, because Send is in the most cases the action which the user wants to take.

Patterns for other groups of disabled persons

Many groups - disabled or not - benefit from a consistent and logical structure of web pages and websites. Such groups are visually impaired, cognitive disabled, persons with memory difficulties and so on.

persons with high degrees of magnification need to memorize the structure of the page, because they can only see a small piece of the page in every moment. Other groups are facing similar problems because of other reasons

Perhaps you already heard of the information architecture. It is a very important topic especially for persons with disabilities, because for many of them the cognitive or per captive requirements are higher than for not disabled persons.

With good information architecture, the user is guided into a learning process, which facilitates him the using of the website.

Images, Signs and symbols

Pattern recognition although is useful in terms of images, signs and symbols. For example, for a visually impaired individual it is often easier to recognize an object like a face on an image, when you tell him what's on the image.

There is a similar effect in case of signs and symbols. You find more than a thousand different fonts in the world. With a few exceptions, most persons can read most letters independently from the chosen font. But for most readers a text is easier to read when they have more experience with this certain font. A special font may improve the look of the text, but it could increase the cognitive effort for the reader.

The same is true for symbols like emoticons or control elements for applications. Well established symbols like the disk for "Save" can reduce the effort for the user, because he knows this symbols out of other contexts. If you draw your own symbols or try to establish a new set of symbols you decrease the Usability of your application.


Patterns are one of the pillars of accessibility and Usability not only for disabled, but for all users. The Styleguides of big software developers like Microsoft and Apple are very recommendable to developers to establish a unique user experience on the whole application.

Developers should not forget that the users only want to take a special action in the shortest possible time, with less effort and errors. They are not much interested to admire the great or exceptional Design of an application.

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