14 DAY TRIAL // The most important aspect regarding accessibility principles in a website navigation system for external links that point to others websites is represented by visual indicators.
There are multiple alternatives to introduce elements indicating in a visual manner details about the new URL where a visitor should navigate. As opposite to popup images or tooltips, the website thumbnail will improve the navigation experience because the visitor will be able to visualize any webpage before executing a HTTP request for its URL.
Website thumbnail is practically a screenshot of a certain web page corresponding to a given URL. The screenshot could have any dimension and its position is recommended to be next to the link pointing to the website URL. For example, website thumbnails are proper to be used in conjunction with the links existing in pages displaying the results of a query for a search engine.
These thumbnails could be created manually with the help of specialized desktop software, but when you have to perform the same operation for a high number of URLs, this procedure is not efficient. The existing web services provide you the alternative to automate this task: usually, you just have to provide the URL in a form field and the dimension of the final screenshot.
Many of the web services that allows you to capture website screenshots offers APIs and other tools, like PHP classes in order to simplify the integration in certain web applications or websites. There are also free applications running on server side that allows you to implement a website thumbnail generation service in your own website, such as the Website Thumb Generator PHP script.
A free and full featured website thumbnail generation service is ShrinkTheWeb that provides almost all necessary options to webmasters. From the practical experience results that, besides the increasing of a certain website accessibility and traffic, website thumbnails usage will generate also high click-through rates.