Some search engines use the information within Alt tags when forming a description and determining the ranking for your site. Alt tags are used to display a description of the graphic they are associated with if the graphic cannot be displayed. Alt tags appear after an image tag and contain a phrase that is associated with the image.
Ensure that your Alt tags contain the keywords assigned to the particular page wherever you can. This gives your page a better chance of being ranked higher in the search engines. For example:
<image src=“images/logo.gif” height=“50” width =“50” alt=“Best Western Hotel Orlando”>
You do not want your Alt tags to look something like “company logo” because this does not include any keywords. Be sure you apply proper Alt tags to all images on your site to achieve best results. Keep in mind that users who browse with graphics disabled must be able to navigate your site, and proper use of Alt tags assists them in doing so.