Friday, April 22, 2011

Alt Attribute & SEO Optimization

SEO Optimization images is becoming more and 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 opportunity for better rankings.

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

Images:. Make use of the alt attribute to provide descriptive text. In addition, we recommend using 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 a similar 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, looking to achieve a certain 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 might create a penalty for your site's ranking. Even without this type of penalty, your site's rankings won't benefit from this plan.
This method also puts persons who use screen readers in a greater disadvantage. Screen readers are software-based tools that actually read aloud the items in what's displayed on the screen. In browsing the web, the alt attributes of images are read aloud too.

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

An ALT attribute should not be used as a description or perhaps a label to have an image, though many people utilize it in that fashion. Though it may appear natural to assume that alternate text is really a label or a description, it is not!

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

The goal would be to supply the same functional information that a visual user would see. The alt attribute text should be the "stand in" when the image itself is unavailable. Think about this: Should you replace the look with the text, would most users get the same basic information, and wouldn't it create the same response?
Some examples:


Some SEO Optimization Tips

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

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

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

If it's meant to convey the use of a function, then the function is what ought to 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 a CSS background image so that reading browsers don't bother users by uttering such things as "spacer image".

Keep in mind that it's the function from the image we are trying to convey. For example; any button images shouldn't include the word "button" within the alt text. They ought to emphasize the action performed through the button.

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

Try to flow alt text with the remainder from the text because that's how it is going to be read with adaptive technologies like screen readers. Someone listening to your page should hardly be aware that a graphic image is there.
Please keep in mind that utilizing an alt attribute for each image is needed to satisfy the minimum WAI requirements, that are used as the benchmark for accessibility laws in UK and also the rest of Europe. They are also required to meet "Section 508" accessibility requirements in the US.

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

Content and Function

I. Eye-Candy

Eye-Candy are things 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 which will boost the usability from the site for someone 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 may actually set the mood or set happens so to speak. These graphics aren't direct content and could not be considered essential, but they're essential in that they help frame what's going on.

Attempt to alt-ify the 2nd group as makes sense and is relevant. There may be instances when doing this might be annoying or detrimental to other users. Then avoid it.

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

Most times it depends on context. Exactly the same image in a different context may require drastically different alt text. Obviously, content ought to always be fully available. How you go in this case is really a judgment call.

III. Content and Function

This is when the image may be the actual content. Always alt-ify content and functional images. Title and long description attributes may 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 are there. You have to figured out precisely what function a picture serves. Consider what it is concerning the image that's important to the page's intended audience.

Every graphic has a reason behind standing on that page: since it either enhances the theme/ mood/ atmosphere or it is critical to what the page is attempting to explain. Understanding what the look is for makes alt text simpler to write. And practice writing them definitely helps.
A way to check the usefulness of alternative text is to imagine reading the page on the phone to someone. What would you say when encountering a specific image to make the page understandable to the listener?

Besides the alt attribute you've got a couple more tools available for images.
First, in level of descriptiveness title is within between alt and longdesc. It adds useful information and can add flavor. The title attribute is optionally rendered through the user agent. Remember they are invisible and never shown as a "tooltip" when focus is received via the keyboard. (So much for device independence). So make use of the title attribute just for advisory information.
Second, the longdesc attribute points towards the Link to a complete description of an image. If the information found in an image is essential to the meaning of the page (i.e. some important content would be lost if the image was removed), a longer description than the "alt" attribute can reasonably display ought to be used. It may provide for rich, expressive documentation of the visual image.

It ought to 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 the image...The goal is by using any period of description essential to impart the details of the graphic.

It would not be remiss to hope that a long description conjures an image - the image - in the mind's eye, an analogy that holds true even for that totally blind."

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

Oftentimes, you are best just choosing your gut instinct -- if it's not necessary to include it, and if you don't possess a strong urge to do it, don't include that longdesc.

However, if it's necessary for the entire page to work, then you have to add 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.

Exactly the same image may require alt text (or title or longdesc) in one spot, although not in another. If the image provides simply no content or functional information alt="" or background CSS images might be appropriate to use. But if the image provides content or adds functional information an alt would be required and perhaps a long description would be in order. Oftentimes this type of thing is really a judgement call.

Image Seo optimization Tips

Listed here are key stages in optimizing images:

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

Label the file extension. For example, if the image internet search engine sees a ".jpg" (JPEG) file extension, it's going 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 at the image that is relevant to that image.
Again, do not lose an excellent chance to help your website together with your images searching engines. Begin using these steps to rank better on all of the engines and drive increased traffic to your site TODAY.

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