a word or phrase that is displayed when a user has image loading disabled in their browser or when a user abandons a page by hitting "stop" in their browser prior to the transfer of all images. Also appears as “balloon text” when a user lets their mouse

descriptive text that is meant to be displayed by the browser when it cannot locate a specific image or other piece of content, or when the user has configured the browser to turn off graphics images. Some search engines will index the contents of ALT text and use it when determining relevancy and ranking.

A description of a hyperlink or image, put in by the author of a Web page, that pops up when you move the mouse pointer over the hyperlink or image.

When you are creating a webpage, you have the option of specifying alternate text for every image you include on your page. This is so that for the people that set their browser so that it won't load any images when it retrieves a web page. This means they don't have to wait for images to download. Also, blind people who are using the web cannot see the images, but their screen reader will pick up and read the alternate text to them so that they know what the picture is of. The alternate text will be read by text-to-speech converters, and, in the latest browsers, the title will appear as a tooltip when you hover over the image.

Text that appears while a banner is loading or when a cursor moves over a banner.