Welcome to w3b-Doctor.com The home of clean simple web design.
This is an often overlooked area of website development. It refers to making websites useable for both able and disabled visitors. Some examples to consider:
Blind or partially sighted users who may not use a standard browser to access your website. Most visually impaired users will use either speech recognition software or screen readers. For these users content is king, the way the site looks is immaterial. Here it is vital to make sure that the page uses semantically meaningful HTML, with text equivalents for all important visual elements and that link text is meaningful.
Deaf users will not be able to understand uncaptioned video or an audio track that doesn't have a text alternative.
Poor motor control, or even arthritis could make certain navigation elements hard to use if they are not of sufficient size.
Colour blind or Colour lazy users will struggle to understand content if the background and foreground have insufficient contrast or uses specific colour combinations.
For dyslexic or users with learning difficulties it is important to make sure that language is as simple as possible. Use of overly complicated terms will only dissuade them from using your website.
For more detailed info please check out the following links:
The alt attribute is used to specify alternative text for elements that are to be rendered onto a page. The most common example is with images, a visually impaired or search engine crawler programme will look for this element to be able to interpret what the image represents.
This is a ranking used by google to weight the importance of a webpage. Many elements contribute to the end score. A much more detailed explanation can be found at wikipedia http://en.wikipedia.org/wiki/PageRank
This refers to the technology that search engines use to catalogue websites. They are one of your most important users as they have the potential to attract more customers to your website through better search engine results. Unlike the vast majority of site visitors though they are not really interested in what colours your site uses, they are only interested in your content and more importantly the quality of said content. If the page is not correctly coded to use semantically meaningful HTML then the crawler will not be able to correctly index the important areas of your site. This is why sites that adhere to accessibility standards tend to rank higher in search results than those which don't.
These are small files stored in your web browser's temporary internet files. They are created by websites to store visitors information. Most reputable websites will store user specific information in them, commonly shopping cart items, language preferences or login information. Without them a website has no memory of who you are. You can set your trust level for general web browsing within your browser's preference settings.
Problems occur when people use them to try to gain access to your web based accounts, or when tracking cookies are used to compile long term browsing histories against a user's knowledge. It is worth reading more about this as it is an important area to understand to safely navigate the web.
The following wikipedia page goes into a lot more detail http://en.wikipedia.org/wiki/HTTP_cookie
This refers to how you want search engine spiders / crawlers to index your website. It can either be set from a special file in the root of your web server called robots.txt or from within the meta data section of each webpage. They basically tell these programs what pages should be indexed and which should not. A more detailed explanation can be found at wikipedia http://en.wikipedia.org/wiki/Robots_exclusion_standard
An example of a robots.txt file could be:
Examples of the meta data approach:
<META NAME="ROBOTS" CONTENT="INDEX, FOLLOW" >
<META NAME="ROBOTS" CONTENT="NOINDEX, NOFOLLOW" >
As far as websites are concerned meta data holds information about the webpage itself, but is not displayed to the user within the webpage itself. It is normally used to give information to the web browser or search engines about what is to be found within the page.
This is not really meta data, but is normally included in the same area of code. It is the text that appears at the top of the web browser when you visit a page. It is a very important element of a webpage as search engines give a high priority to the text within this tag. It is not however wise to stuff this tag full of unrelated content as the search engines look for the content of this title tag to be repeated within the content of the webpage itself.
This tag is generally used in the search engines results page. Unless the search engine feels that an abstract from the content of the page better fits the search query.
This tag as it suggests stores a list of keywords, or search phrases that the page should match to. Due to abuse in the past, this tag now has limited use. Make sure that any keywords used in this tag can be found within the content of the webpage. Otherwise it is likely that search engines will just ignore this tag.
This is a more recent addition and is really coming in as a result of mobile platforms. This tag allows your site to be given a physical location which may be used to display a business for example on a mapping application.