About Me 0085: Alt Attribute & SEO Optimization

SEO Optimization images has become increasingly more essential in SEO (Seo optimization) for websites. The ALT attribute is a critical step that is sometimes forgotten. This is often a lost opportunity for better rankings.

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

Images:. Make use of the alt attribute to provide descriptive text. Additionally, we recommend using a human-readable caption and descriptive text around 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 using this attribute, attempting to stuff it with keywords, looking to achieve a certain keyword density, which is not as relevant for rankings now as 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 your site's ranking. Even without such a penalty, your site's rankings will not 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 is displayed on the screen. In browsing the net, the alt features of images are read aloud as well.

Imagine listening to 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 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 for the reason that fashion. Though it might seem natural to assume that alternate text is a label or a description, it's not!

The words used inside 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 would be to supply the same functional information that a visual user would see. The alt attribute text should function as a "stand in" when the image itself is not available. Think about this: Should you replace the look using the text, would most users receive the same basic information, and would it create the same response?
Some 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 the image is meant to convey the literal items in the image, then a description is suitable.

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

If it's designed to convey using a function, then your function is what ought to be used.

Some Alt Attribute Guidelines:

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

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

Keep in mind that it is the function from the image we are trying to convey. For instance; any button images shouldn't range from 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 need drastically different alt text.

Attempt to flow alt text with the remainder of the text because that is the way 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 can there be.
Please keep in mind that using 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 also the remainder 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:

Eye-Candy
Mood-Setting
Content and Function

I. Eye-Candy

Eye-Candy are things 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 might be value to a sighted user).

Never alt-ify eye-candy unless there is something there which will enhance the usability from the site for someone using 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 mood or set happens so to speak. These graphics are not 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 times when doing this may be annoying or detrimental to other users. Then avoid it.

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

Most times it depends on context. Exactly the same image in a different context may need 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 is the actual content. Always alt-ify content and functional images. Title and long description attributes can also be in order.
The reason many authors can't figure out why their alt text isn't working is that they don't know why the images exist. You need to determined precisely what function a picture serves. Consider what it's concerning the image that's vital that you 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 advisable to what are the page is trying to explain. Understanding what the look is perfect for makes alt text easier to write. And practice writing them definitely helps.
A way to check the usefulness of alternative text is to imagine reading the page over the telephone to someone. An amount you say when encountering a particular image to make 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 in 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 not shown as a "tooltip" when focus is received through the keyboard. (So much for device independence). So use 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 a picture is important to 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 offer rich, expressive documentation of a 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 really a long description of an image...The goal is by using any length of description essential to impart the facts from the graphic.

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

Although the 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 going with your gut instinct -- if it's not necessary to incorporate it, and when you don't possess a strong urge to get it done, don't add that longdesc.

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

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

The same image may require alt text (or title or longdesc) in one spot, but not in another. If the image provides absolutely no content or functional information alt="" or background CSS images may be appropriate to make use of. But if the image provides content or adds functional information an alt would be required and perhaps a long description will be in order. In many cases this kind of thing is a judgement call.