Alt tags is actually an abbreviation for ‘alternative tags’. Sometimes referred to as ‘alt text’, ‘alt descriptions’ or ‘alt attributes’. Alt tags are used with the HTML code to create a description of images and videos. In doing this, you allow a web crawler to know exactly what content is on the page without having to actually see the visual aspects. This is also great for SEO because you can optimise your alt tags to contain relevant keywords as long as they describe the images truthfully.