What is an alt tag and how does it affect SEO?
Definition: An alt tag, also known as an “alt attribute”, is an HTML attribute applied to image tags to provide a textual alternative to search engines. Applying alt tags to images, such as product photos, can positively affect your SERP.
Code sample: <img src=”pic_mountain.jpg” alt=”Mountain View”>
What is the purpose of alt tags?
Search engines and other robots cannot interpret or understand the meaning of images although images can play a crucial role in the way a particular website is interpreted. Alt tags address this by providing a textual description that search engines can understand. When Googlebot or other crawlers browse the page, images with properly formatted alt text help to better index the page and give it a better place in search results.
In that sense, alt text offers you another opportunity to include your target keyword. With on-page keyword usage still pulling weight as a search engine ranking factor, it’s in your best interest to create alt text that both describes the image and, if possible, includes a keyword or keyword phrase you’re targeting.
Alt tags are also useful for users who view the webpage on screen readers or browsers that cannot process images.