What are ALT Tags for Images?
ALT tags are probably one of the most under-utilized html tags for easy free keywords on the internet. If you are not sure what an ALT tag is I will give you a quick example; it is an HTML tag used on images and usually is right next to the “Title” tag and stands for alternate text.
ALT Tags are not required and most of the time they are either blank alt=”” or sometimes there is no alt tag at all. The great thing about ALT tags are that you can embed keyword strings that are as long as title tags, up to 70 characters and the text does not appear visibly anywhere but Google will crawl your site and hit on all of the keywords in the ALT tag. ALT tags are also used by Google images for classification and tagging purposes.
Best Practices for ALT Tags
As you can see from the above screenshot, I have embedded some of my target search phrases into the ALT tag text of one example image on my website. I would recommend to not use the same search phrases on every image, but to mix them up between different combinations of search phrases and in different orders, my experience has shown me that this is more effective. I look at ALT tags in the same way I look at a Title tags when populating the search phrases and keywords, but ALT tags obviously have much less importance than title tags.
My view is the more keywords and optimization the better, so utilize ALT Tags on all of your images to get free additional keywords and maximize your on page SEO!