An "alt tag" is a short description given to an image on a website. It helps people who cannot see the image understand what it looks like by using text.
Sentences with «alt tag»
Using alt tags solely for search engine optimization purposes is generally discouraged. (customlegalmarketing.com)
Adding the title tags and alt tags really help. (quicksprout.com)
If you are already optimizing your images for image search, you probably are doing so through alt tags and image file names. (quicksprout.com)