SEO: Why you should never forget your ALT tags

Despite what all the search engine companies like to say, the technology behind image searching is very much in its infancy and it will be a long while yet before any algorithims – or computers for that matter – will be able to sucessfully recognise and image based on its content.

Quite simply, our human minds are hard-wired – from a very early age – to recognise and evaluate visual imagery. A three year old may not be able to tell you how a car’s engine works, but they will be able to tell you the difference between a cow and a car.

For computers, it’s not so easy. While search engine are slowly building their abilities to analyse textual content, they have a long way to go with images, and don’t expect a solution soon. Even Google – the mighty king of online search – still uses human editors to sucessfully tag the important aspects of any online images.

For SEO practioners, it’s critical to remember this. Search engines simply don’t – and can’t – recognise just what that image is you’re putting up on that website. Thankfully, HTML has always provided a good meta attribute to help the search engines out. It’s called the ALT tag (which means alternative). It’s purpose was originally singular: to help out vision impaired users and those who surfed the web with image loading turned off. Yes, people actually chose to do that back in the early days of dial up internet access, it made browsing so much quicker (note: this has never applied to those users browsing for, um, cough, adult content).

By effictivley using the ALT tag, you are not only helping out those who may be vision impaired, but also helping to give search engines a helping hand. But don’t get greedy. Nothing tells a search engine you’re up to no good by stuffing your ALT tags with excessive keywords, or worse still, keywords which have no relation whatsoever to the image’s content. As image recognition is still a far away technology, search engines still rely very heavily on humans for the grunt work, and while it may be possible to fool a blind search engine bot, a human will quickly recognise that picture of a toaster is indeed not related to Britany Spears.

Good search engine optimisation is not just about textual content (although it still primarily is). It’s also about making sure all your elements, from the code base, to the structure, to any other content, such as image, is tagged and categorised. Therefore the ALT tag is just tool you can use in your optimisation strategy.