About Me 0001: Alt Attribute & SEO Optimization

SEO Optimization images has become increasingly more essential in SEO (Search Engine Optimization) for websites. The ALT attribute is a critical step that is often overlooked. This can be a lost chance of better rankings.

In Google's webmaster guidelines, they advise the use of alternative text for the images in your site:

Images:. Make use of the alt attribute to supply descriptive text. Additionally, we recommend utilizing a human-readable caption and descriptive text round the image.

Why would they ask us to do that? The answer is easy, really; search engines have the same problem as blind users. They cannot begin to see the images.

Many webmasters and inexperienced or unethical SEOs abuse the use of this attribute, trying to stuff it with keywords, hoping to achieve a particular keyword density, which isn't as relevant for rankings now as it once was.

On the other hand, high keyword density can, on some search engines, trigger spam filters, which may result in a penalty for the site's ranking. Even without such a penalty, your site's rankings won't benefit from this plan.
This process also puts persons who use screen readers at a greater disadvantage. Screen readers are software-based tools that actually read aloud the contents of what's displayed on the screen. In browsing the net, the alt attributes of images are read aloud too.

Imagine listening to a paragraph of text that is then repetitions of many keywords. The page will be not even close to accessible, and, to put it bluntly, will be found quite annoying.
What exactly is an Alt attribute?

An ALT attribute shouldn't be used like a description or a label to have an image, though lots of people utilize it in that fashion. Though it may appear natural to assume that alternate text is a label or a description, it's not!

The words used inside an image's alt attribute ought to be its text equivalent and convey the same information or serve the same purpose that the image would.

The thing would be to provide the same functional information that a visual user would see. The alt attribute text should function as a "stand in" when the look itself is not available. Ask yourself this question: If you were to replace the look using the text, would most users receive the same basic information, and wouldn't it generate the same response?
Some examples:

Some SEO Optimization Tips

If a search button is really a magnifier or binoculars its alt text ought to be 'search' or 'find' not 'magnifying glass' or 'binoculars'.

If the image is supposed to convey the literal items in the image, a description is appropriate.

If it is meant to convey data, then that information is what is appropriate.

If it is meant to convey the use of a function, then your function is what should be used.

Some Alt Attribute Guidelines:

Always add alt attributes to images. Alt is mandatory for accessibility as well as for valid XHTML.

For images that play only a decorative role in the page, make use of an empty alt (i.e. alt="") or perhaps a CSS background image to ensure that reading browsers don't bother users by uttering things like "spacer image".

Keep in mind that it is the function from the image we are attempting to convey. For instance; any button images should not include the word "button" within the alt text. They should emphasize the action performed by the button.

Alt text ought to be determined by context. The same image in a different context may require drastically different alt text.

Attempt to flow alt text with the rest from the text because that's the way it will be read with adaptive technologies like screen readers. Someone listening to your page should hardly be aware that a graphic image can there be.
Please keep in mind that utilizing an alt attribute for every image is required to satisfy the minimum WAI requirements, which are used as the benchmark for accessibility laws in UK and the remainder of Europe. Also, they are required to meet "Section 508" accessibility requirements in america.

It is important to categorize non-text content into three levels:

Eye-Candy
Mood-Setting
Content and Function

I. Eye-Candy

Eye-Candy are stuff that serve no purpose other than to make a site visually appealing/attractive and (in many cases) satisfy the marketing departments. There isn't any content value (though there might be value to a sighted user).

Never alt-ify eye-candy unless there's something there that will enhance the usability of the site for somebody using a non-visual user agent. Make use of a null alt attribute or background images in CSS for eye-candy.

II. Mood-Setting

This is the middle layer of graphics which may actually set the atmosphere or set the stage as it were. These graphics aren't direct content and could 't be considered essential, but they are important in they help frame what's going on.

Attempt to alt-ify the second group as is sensible and is relevant. There may be times when doing this may be annoying or detrimental with other users. Then try to avoid it.

For instance; Alt text that is identical to adjacent text is unnecessary, and an irritant to screen reader users. I recommend alt="" or background CSS images in such instances. But sometimes, it's important to understand this content inside for all users.

Usually this will depend on context. Exactly the same image in a different context may need drastically different alt text. Obviously, content should always be fully available. How you go in this case is really a judgment call.

III. Content and Function

This is where the look is the actual content. Always alt-ify content and functional images. Title and long description attributes can also be so as.
The main reason many authors can't understand why their alt text isn't working is that they don't know why the pictures exist. You need to determined precisely what function an image serves. Consider what it's concerning the image that's important to the page's intended audience.

Every graphic has a reason for being on that page: because it either enhances the theme/ mood/ atmosphere or it is critical to what are the page is trying to explain. Knowing what the look is for makes alt text easier to write. And exercise writing them definitely helps.
A method to check the usefulness of alternative text would be to imagine reading the page over the telephone to someone. An amount you say when encountering a specific image to create the page understandable to the listener?

Besides the alt attribute you've got a couple more tools at your disposal for images.
First, in degree of descriptiveness title is within between alt and longdesc. It adds useful information and may add flavor. The title attribute is optionally rendered by the user agent. Remember they're invisible and not shown like a "tooltip" when focus is received through the keyboard. (So much for device independence). So make use of the title attribute only for advisory information.
Second, the longdesc attribute points towards the Link to a full description of an image. If the information contained in a picture is important to the concept of the page (i.e. some important content would be lost when the image was removed), a longer description than the "alt" attribute can reasonably display should be used. It may offer rich, expressive documentation of a visual image.

It should be used when alt and title are insufficient to embody the visual qualities of an image. As Clark [1] states, "A longdesc is a long description of an image...The aim is by using any length of description necessary to impart the details from the graphic.

It wouldn't be remiss to hope that the long description conjures a picture - the look - within the mind's eye, an analogy that is true even for that totally blind."

Even though alt attribute is mandatory for web accessibility and for valid (X)HTML, not all images need alternative text, long descriptions, or titles.

In many cases, you're best just choosing your gut instinct -- if it's not essential to incorporate it, and if you don't possess a strong urge to do it, don't include that longdesc.

However, if it's essential for the whole page to work, then you've to include the alt text (or title or longdesc).

What's necessary and what's not depends a great deal on the function of the image and it is context about the page.

The same image may need alt text (or title or longdesc) in a single spot, but not in another. If an image provides absolutely no content or functional information alt="" or background CSS images might be appropriate to make use of. However, if the image provides content or adds functional information an alt will be required and perhaps even a long description would be so as. Oftentimes this type of thing is really a judgement call.