Each image in your website can be referenced by an Alt text description that gives your site visitors a text description of the image when the hover their mouse over it. This may not look very helpful at first unless the user is visually impaired but a closer examination on how search engines find information online will help you understand its importance. Search engines (Google’s crawlers) cannot read images but image titles and descriptions.
It becomes apparent then that optimizing alt texts can prove very helpful in terms of Search engine optimization for your website. Your Image Alt text will help search engines understand the message you are trying to convey through the image displayed. Though image Alt text descriptions is weighted of less importance than actual readable text in the eyes of the search engines it is still an important task to be considered carefully by SEO professionals.