Alt-Text: The alt attribute is used to place text behind an image on a web page. The content of the alt attribute is shown as a tool tip when an Internet user places his/her mouse pointer over the image.
The alt attribute is used to increase the textual richness of a web site. Originally, it was implemented for people with slow Internet connections or text-only browsers. The more textual information a web site contains, the easier it is for the search engines to locate the site to index.
Another use for alt-text is to increase the accessibility of a site to visually impaired users, by allowing speech browsers to describe the site to them.
Keep alt-text relevant to the content of your site.
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