Seen but not heard – images and findability

As the old proverb goes “A picture is worth a thousand words”, but in the world of successful websites this only holds true if someone can find it and see it.

When it comes to adding content to your website imagery is an invaluable tool for creating a visual impact, setting the theme of your site (and your company) or showing off your high-quality products. However, all of that is only possible once someone has found your site and decided to pay it a visit.

As Keith discussed in our last SEO feature one of the keys to creating a successful website is making sure it is easy for search engines to understand and describe to the audience. In essence, creating a user-experience that says the right things to your customers but in a way that also talks to the search engines, which in turn will bring those customers to you.

So what part do images play in talking to search engines and getting traffic to your site? Well, only a supporting role it has to be said, but here is an explanation of how they can play that role well.

Search engines and web content

A search engine’s goal is to provide the user with the best possible answer to the question they ask. They achieve this by sending out software programmes known as ‘robots’ or ‘spiders’ to crawl across the web tirelessly, analysing sites and indexing the results into their databases, ready to provide to a searcher on request.

This interaction between websites and spiders means the goal of a business wanting to be findable is to ensure all content is available for search engines to properly analyse and accurately index. A practice known as ‘being search engine friendly’.

Your content (text, images, multimedia etc. all combined), is essentially the message you want to communicate to your audience. So, you want to make sure the whole message goes out intact to as many people as possible. Search engines will happily do this on your behalf but will only pass on the message you give to them.

Using images to get your message across

The power of imagery — such as photos, your company’s branding or information graphics — will get the message across quickly to someone visiting your site. Although to a search engine spider, which deals in text and can’t see the contents of an image, the message stops dead.

If part of your message is only conveyed by imagery this important information will not be picked up and understood by search engines, and in turn will not be passed on to search engine users. Effectively lost in translation.

A good example would be Company-X creating an advert for a special offer they’re running on widgets. They produce an eye-catching photo of their top-of-the-range widget with the words: “Half price widgets this month only!” beautifully typeset in the graphic and publish it right in the middle of their homepage.

Unfortunately for Company-X, a search engine spider would not view the image and would simply log the fact that it’s there. The important message that “widgets are half price this month!” would not make it through to the hordes of eager widget-buyers searching the web for the best place to buy new widgets.

Providing text equivalents of non-text content

So how could Company-X make their images search engine friendly and get their important message picked up by text-only spiders? Quite simply, by optimising their images and providing text equivalents.

There are a number of ways to reinforce images with text content, ready and waiting for search engines to pick up and pass on to searchers:

• The ‘Alt’ (Alternate) attribute
  An ‘Alt’ attribute is used in HTML and XHTML to attach a text alternative to images in web pages. This allows the content editor to add a short description explaining the meaning of the image for users who can’t see it. This feature was initially designed to cater for blind users or those who have set their browser not to display images, but it is also the foremost way to explain the content of your images to search engine spiders.
• Captions and surrounding text
  Search engine spiders also look at your page for text surrounding an image as a way of working out what that image is about. In some cases it is worthwhile to include a caption next to your image. This lets you associate more information with the image that may not necessarily explain what the image is showing, but explains more about why the image is on the page.
• Image filenames
  While spiders are not able to see what is in an image, they will find the image and are perfectly able to read its filename. So bear this in mind when you’re naming the image files for use on your site. As far as search engines listings are concerned an image named ‘widget-sale-Jan2008.jpg’ will be much more explanatory than ‘widgets.jpg’.

In this example from the BBC you will see two of the above methods in action. The logo image for this UK television programme describes the subject of the article visually. The image then has the alternate text “Ski Sunday”, communicating this same theme to search engines. It is also connected to a caption reading: “Ski Sunday returns to BBC Two on 20 January”, which adds more context to the image and its relation to the story.

So that wraps up our intro on making images work for you (rather than against you), when it comes to SEO. The aim for this article was to show you the ‘what’ and ‘why’ of optimising images for search engines. Keep an eye on this SEO series for follow-up posts explaining more on the ‘how’ of working with images.

This entry was posted by Posted by Doug on Monday, January 14th, 2008 at 10:08 pm, and is filed under SEO, Working with images. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.