A few weeks ago I wrote a post about optimizing page titles. Another easy technique that can help your website get better rankings in search engines is to add alt attributes to images. Here is what we can find on the topic in Google’s Webmaster Guidelines: “Try to use text instead of images to display important names, content, or links. The Google crawler doesn’t recognize text contained in images. If you must use images for textual content, consider using the alt attribute to include a few words of descriptive text”. Fair enough, that’s pretty straight forward.

Alt attributes will help search engines know what the images are about, but also web users in the case they don’t display (the alt attributes will show up instead of the images). I don’t think you should just add as many keywords as possible, but rather give the image a  relevant description. If you use a content management system, it should be fairly easy. You may simply have to go the image’s properties. There’s probably a blank field dedicated to the alt attribute. If you don’t use a content management system, it may be a little more difficult as you have to use an HTML editor and add alt="..." within the image tag. You may also want to add title attributes (title="..."), which are used by most web browsers as tooltips. Tooltips show up when you hover an image with your mouse pointer. Some web browsers, including Internet Explorer 6 and 7, use alt attributes (and not title attributes) as tooltips.

This will look like a tip for beginners, and it is the case, but I still see a lot of websites with no alt attributes at all… and I think that’s a shame, because it is useful to both search engines and web users. I wouldn’t say all images should have alt attributes but most of them, especially your logo, product images, etc.