Lightning effects: 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 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 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 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, hoping to achieve a particular keyword density, which is not as relevant for rankings now as it was previously.

On the other hand, 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 take advantage of this plan.
This process also puts persons who use screen readers at a greater disadvantage. Screen readers are software-based tools that really 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 hearing a paragraph of text that is then repetitions of many keywords. The page would be far from accessible, and, to put it bluntly, will 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 lots of people utilize it in that fashion. Although it might seem natural to assume that alternate text is really 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 exactly the same information or serve the same purpose that the image would.

The goal would be to provide the same functional information that the visual user would see. The alt attribute text should be the "stand in" when the look itself is unavailable. Ask yourself 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 really a magnifier or binoculars its alt text should be 'search' or 'find' not 'magnifying glass' or 'binoculars'.

If the image is meant to convey the literal contents of the image, then a description is appropriate.

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

If it is designed to convey the use of 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 as well as for valid XHTML.

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

Remember that it's the function of the image we're trying to convey. For example; any button images shouldn't include 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.

Attempt to flow alt text with the remainder of the text because that's 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 utilizing an alt attribute for every image is needed to meet the minimum WAI requirements, that 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 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 isn't any content value (though there may be value to some sighted user).

Never alt-ify eye-candy unless there is something there which will enhance the usability of the site for someone utilizing 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 actually the middle layer of graphics which might actually set the atmosphere or set the stage so to speak. These graphics are not direct content and could not be considered essential, but they are important in they help frame what's 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 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 instances. But sometimes, it's vital that you understand this content in there for all users.

Usually this will depend on context. 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 example is 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 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 pictures are there. You have to determined precisely what function an image serves. Think about what it is 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 improves the theme/ mood/ atmosphere or it is critical to what the page is attempting to explain. Understanding what the image is perfect for makes alt text easier to write. And exercise 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 specific image to create the page understandable towards the listener?

Besides the alt attribute you've got a couple more tools at your disposal for images.
First, in level of descriptiveness title is in between alt and longdesc. It adds useful information and can add flavor. The title attribute is optionally rendered by the user agent. Remember they're invisible and never shown as a "tooltip" when focus is received through 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 the image. When the information contained in an image is essential to the meaning of the page (i.e. some important content would be lost when the image was removed), an extended description than the "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 an image. As Clark [1] states, "A longdesc is a long description of an image...The goal is by using any period of description necessary to impart the details from the graphic.

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

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

Oftentimes, you're better off just choosing 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 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 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 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 so as. In many cases this type of thing is a judgement call.