For a long time, search engines found it very difficult to read any information and links which do not appear in HTML format within a page’s source code. This applied predominantly to interactive or multimedia content, though not exclusively so. The continuing development of Google Image Search, which is becoming integral to the search engine’s algorithms, has improved this somewhat.
These technologies can be aesthetically beneficial to a website, offering eye-catching content in a format that goes beyond simple text. However, it is important not to overuse them and couple them with relevant, well-researched onsite copy which can be crawled by Google’s spiders.
AJAX raises even greater problems, as it changes content on a page without changing the page’s URL. Consequently, search engines are unable to index it. Google had developed a way to crawl AJAX-enhanced pages in 2009, but ceased recommending the use of AJAX in 2015, although tests have shown that Google is still able to crawl these pages. In order to be certain that your site will be comprehensively crawled while still featuring AJAX, your agency will be able to build new URLs for the differing versions of your content, and conduct standard redirects to them from other areas of the site using standard HTML.
Flash once lived up to its name: Its eye-catching animations were an immediate way to grab a user’s attention. Unfortunately, using Flash also gives your website minimal attention from Google. Search engines are unable to ‘guess’ at the content contained in Flash, and as a result, text contained in Flash animations will not rank in search engine results pages.
As search technology continues to evolve, search spiders are beginning to identify some of the content contained in videos and images. Optical Character Recognition (OCR) is already very much in play, allowing spiders to read images contained in un-spiderable content—to an extent.
With the improvements to Google Image Search, Google can also match pictures based upon their content, as opposed to solely relying on alt text or written description. This recognition of increasingly complex shapes and colours is a major step-forward, and the first real evidence of Google’s step away from a purely HTML-reliant search engine.