Package Research: Alt Attribute & Search engine optimization

SEO Optimization images has become more and more essential in SEO (Search Engine Optimization) for websites. The ALT attribute is really a critical step that is sometimes forgotten. This can be a lost opportunity for better rankings.

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

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

Why would they ask us to achieve that? The answer is simple, really; search engines like google 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, trying to stuff it with keywords, hoping to achieve a particular keyword density, which is not as relevant for rankings now since it once was.

On the other hand, high keyword density can, on some search engines like google, trigger spam filters, which might result in a penalty for your site's ranking. Even without this type of penalty, your site's rankings won't benefit from this tactic.
This process 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 shown on the screen. In browsing the web, the alt features of images are read aloud as well.

Imagine hearing a paragraph of text which is then repetitions of many keywords. The page will be far from accessible, and, to put it mildly, will be found quite annoying.
What is an Alt attribute?

An ALT attribute shouldn't be used like a description or perhaps a label for an image, though lots of people utilize it in that fashion. Though it might seem natural to assume that alternate text is a label or perhaps a description, it's not!

What used inside an image's alt attribute ought to be its text equivalent and convey the same information or serve the same purpose the image would.

The goal would be to supply the same functional information that the visual user would see. The alt attribute text should be the "stand in" when the look is not available. Ask yourself this: If you were to replace the image 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 magnifying glass or binoculars its alt text should be 'search' or 'find' not 'magnifying glass' or 'binoculars'.

If the image is supposed to convey the literal contents of the look, then 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 the function itself is what should 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 only 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 do not bother users by uttering things like "spacer image".

Remember that it's the function from the image we are attempting to convey. For instance; any button images should not 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. Exactly the same image inside a different context may need drastically different alt text.

Attempt 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 be aware that a graphic image can there be.
Please remember that using an alt attribute for each image is needed to meet the minimum WAI requirements, that are used as the benchmark for accessibility laws in UK and also the rest of Europe. They are also necessary to meet "Section 508" accessibility requirements in the US.

It is useful 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 make a site visually appealing/attractive and (in many cases) fulfill the marketing departments. There is no content value (though there might be value to some sighted user).

Never alt-ify eye-candy unless there's something there that will boost the usability of the site for somebody using 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 actually set the mood or set happens as it were. These graphics are not direct content and may not be considered essential, but they're essential in they help frame what is going on.

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

For example; 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 important to get this content in there for those users.

Most times this will depend on context. Exactly the same image inside a different context may need drastically different alt text. Obviously, content should always be fully available. The way you use this case 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 understand why their alt text isn't working is that they don't know why the images are there. You need to determined precisely what function a picture serves. Think about what it is concerning the image that's vital that you the page's intended audience.

Every graphic includes a reason behind standing on that page: since it either enhances the theme/ mood/ atmosphere or it is critical to what the page is trying to describe. Understanding what the look is for makes alt text easier to write. And practice writing them definitely helps.
A method to look into 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 create the page understandable towards the listener?

Besides the alt attribute you have a couple more tools available 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 are invisible and not shown as 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 to the Link to a complete description of the image. If the information found in an image is important towards the meaning of the page (i.e. some important content will be lost if the image was removed), an extended description than the "alt" attribute can reasonably display should be used. It can offer 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 really a long description of an image...The aim is by using any period of description essential to impart the details from the graphic.

It would not 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 the totally blind."

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

In many cases, you're better off just choosing your gut instinct -- if it's not essential to include it, and if 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 work, then you've to include the alt text (or title or longdesc).

What's necessary and what's not depends a lot on the function of the image and its context about 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 may be appropriate to use. But if the image provides content or adds functional information an alt will be required and perhaps a long description would be so as. Oftentimes this kind of thing is really a judgement call.