Friday, April 22, 2011

Alt Attribute & SEO Optimization

SEO Optimization images has become increasingly more important in SEO (Seo optimization) for websites. The ALT attribute is a critical step that is often overlooked. This is often a lost chance of better rankings.


In Google's webmaster guidelines, they advise using alternative text for that images in your site:

Images:. Make use of the alt attribute to provide descriptive text. In addition, we recommend utilizing a human-readable caption and descriptive text around the image.

Why would they ask us to do that? The answer is simple, really; search engines have a similar problem as blind users. They can't see the images.

Many webmasters and inexperienced or unethical SEOs abuse the use of this attribute, attempting to stuff it with keywords, looking to achieve a particular keyword density, which is not 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 tactic.
This method 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 is displayed on the screen. In browsing the web, the alt features of images are read aloud too.

Imagine listening to a paragraph of text which is followed by repetitions of numerous keywords. The page will be not even close to accessible, and, to put it mildly, will be found quite annoying.
What is an Alt attribute?

An ALT attribute should not be used like a description or a label to have an image, though many people utilize it for the reason that fashion. Though it might seem natural to assume that alternate text is really a label or a description, it's not!

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

The thing is to supply the same functional information that the visual user would see. The alt attribute text should be the "stand in" when the image is not available. Think about this: If you were to replace the image using the text, would most users receive the same basic information, and wouldn't it create the same response?
A few examples:

 

Some SEO Optimization Tips

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

If an image is meant to convey the literal items in the image, a description is suitable.

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

If it is designed to convey using 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 merely a decorative role in the page, use 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's the function of the image we are trying to convey. For example; 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 based on context. Exactly the same image inside a different context may require drastically different alt text.

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

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 create a site visually appealing/attractive and (oftentimes) satisfy the marketing departments. There is no content value (though there may be value to some sighted user).

Never alt-ify eye-candy unless there's something there which will boost the usability of the site for somebody utilizing a non-visual user agent. Use a null alt attribute or background images in CSS for eye-candy.

II. Mood-Setting

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

Try to alt-ify the 2nd group as is sensible and it is relevant. There may be instances when doing so might be annoying or detrimental with other users. Then try to avoid it.

For instance; Alt text that's just like adjacent text is unnecessary, as well as an irritant to screen reader users. I recommend alt="" or background CSS images in such cases. But sometimes, it's vital that you understand this content inside for all users.

Usually this will depend on context. The same image inside a different context may need drastically different alt text. Obviously, content should always be fully available. How you use this case is a judgment call.

III. Content and Function

This is when the look is the actual content. Always alt-ify content and functional images. Title and long description attributes may also be so as.
The reason many authors can't figure out why their alt text isn't working is that they don't know why the images are there. You need to figured out precisely what function an image serves. Consider what it's about the image that's vital that you the page's intended audience.

Every graphic includes a reason behind being on that page: since it either enhances the theme/ mood/ atmosphere or it is advisable to what the page is trying to describe. Knowing what the look is perfect for makes alt text easier to write. And practice writing them definitely helps.
A way to look into the usefulness of alternative text would be to imagine reading the page over the telephone to someone. An amount you say when encountering a particular image to make the page understandable towards the listener?

Aside from the alt attribute you've got a couple more tools available 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 never shown like a "tooltip" when focus is received through the keyboard. (A lot for device independence). So make use of the title attribute only for advisory information.
Second, the longdesc attribute points towards the URL of a complete description of the image. If the information found in an image is essential towards the meaning of the page (i.e. some important content would be lost when the image was removed), an extended description compared to "alt" attribute can reasonably display ought to be used. It can provide for rich, expressive documentation of a visual image.

It should be used when alt and title are insufficient to embody the visual qualities of the image. As Clark [1] states, "A longdesc is really a long description of the image...The aim is to use any period of description necessary to impart the facts 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 the totally blind."

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

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

However, if it's essential for the entire page to operate, then you have to include the alt text (or title or longdesc).

What's necessary and what's not depends a great deal about the function of your image and its 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 simply no content or functional information alt="" or background CSS images might be appropriate to make use of. But if the image provides content or adds functional information an alt will be required and perhaps even a long description will be so as. In many cases this type of thing is really a judgement call.

Image Search Engine Optimization Tips


Listed here are key stages in optimizing images:

Select a logical file name that reinforces the keywords. You can use hyphens within the file name to isolate the keyword, but avoid to exceeding two hyphens. Stay away from underscores like a word separator, like for example "brilliant-diamonds.jpg";

Label the file extension. For instance, if the image search engine sees a ".jpg" (JPEG) file extension, it's likely to assume that the file is a photo, and if it sees a ".gif" (GIF) file extension, it's going to assume that it is a graphic;

Make sure that the text nearby the image that is highly relevant to that image.
Again, don't lose a great chance to help your website with your images searching engines. Use these steps to rank better on all of the engines and drive more traffic to your site TODAY.

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