Friday, April 22, 2011

Alt Attribute & SEO Optimization

SEO Optimization images is becoming more and more important in SEO (Search Engine Optimization) for websites. The ALT attribute is a critical step that is sometimes forgotten. This can be 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 using 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 like google have the same problem as blind users. They cannot 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 is not as relevant for rankings now since it was previously.

On the contrary, high keyword density can, on some search engines like google, trigger spam filters, which might create a penalty for the 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 contents of what's shown 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 would be not even close to accessible, and, to put it bluntly, would be found quite annoying.
What exactly is an Alt attribute?

An ALT attribute shouldn't be used as a description or perhaps a label to have an image, though many people use it in that fashion. Though it may appear natural to assume that alternate text is a label or perhaps 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 the image would.

The thing would be to supply the same functional information that a visual user would see. The alt attribute text should be the "stand in" in the event that the look itself is not available. Ask yourself this: If you were to replace the image with the text, would most users get the same basic information, and would it generate the same response?
A few examples:

 

Some SEO Optimization Tips

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

If an image is supposed to convey the literal items in the look, then a description is suitable.

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 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 within the page, make use of an empty alt (i.e. alt="") or a CSS background image to ensure that reading browsers don't bother users by uttering such things as "spacer image".

Keep in mind that it is the function of the image we are attempting to convey. For example; any button images should not range from the word "button" in the alt text. They ought to emphasize the action performed through the button.

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

Try to flow alt text with the remainder of the text because that is how it will be read with adaptive technologies like screen readers. Someone hearing your page should hardly remember that a graphic image is there.
Please keep in mind that utilizing an alt attribute for each image is required to meet the minimum WAI requirements, that are used as the benchmark for accessibility laws in UK and the rest 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 apart from to create a site visually appealing/attractive and (oftentimes) satisfy the marketing departments. There is no content value (though there might be value to a sighted user).

Never alt-ify eye-candy unless there is something there which will enhance 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 the middle layer of graphics which might actually set the atmosphere or set the stage so to speak. These graphics aren't direct content and may not be considered essential, but they're important in they help frame what is going on.

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

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

Most times it depends on context. Exactly the same image inside a different context may require drastically different alt text. Obviously, content ought to always be fully available. How you use this example 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 reason many authors can't understand why their alt text isn't working is they don't know why the images exist. You have to figured out precisely what function an image serves. Consider what it is about the image that's important to the page's intended audience.

Every graphic has a reason for standing on that page: because it either improves the theme/ mood/ atmosphere or it is advisable to what the page is attempting to explain. Knowing what the look is perfect for makes alt text simpler 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 particular image to create the page understandable to the listener?

Besides 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 can add flavor. The title attribute is optionally rendered through the user agent. Remember they're invisible and never shown like a "tooltip" when focus is received via the keyboard. (A lot for device independence). So make use of the title attribute just for advisory information.
Second, the longdesc attribute points to the Link to a full description of an image. If the information found in an image is important 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 should be used. It may provide for rich, expressive documentation of the 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 an image...The goal is by using any length of description necessary to impart the details of the graphic.

It wouldn't be remiss to hope that a long description conjures a picture - 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 and for valid (X)HTML, not all images need alternative text, long descriptions, or titles.

Oftentimes, you are best just going with 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've to add the alt text (or title or longdesc).

What's necessary and what's not depends a lot about the function of the image and its context on the page.

Exactly the same image may need alt text (or title or longdesc) in a single spot, but not in another. If the image provides simply no content or functional information alt="" or background CSS images might be appropriate to use. However, if the image provides content or adds functional information an alt would be required and maybe even a long description would be in order. Oftentimes this type of thing is 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 in the file name to isolate the keyword, but avoid to exceeding two hyphens. Avoid using underscores like a word separator, like for example "brilliant-diamonds.jpg";

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

Make sure that the text nearby the image that is relevant to that image.
Again, do not lose a great opportunity to help your website with your images in search engines. Use these steps to rank better on all of the engines and drive more traffic for your site TODAY.

No comments:

Post a Comment