Alt text is a shortened term that stands for alternative text or alt attribute. The alt text is used in HTML and XHTML documents to specify text for an image on a web page in the event that images are turned off on a visitor’s web browser. This text description provided by alt text is generally visible when a visitor “hovers” or holds their cursor over the place where the picture should be. Then a small box with the alt text will appear so that the visitor to the website can read a description of the picture. This tag is also very important for Internet use by the visually impaired, because it allows special software to read the alt text out loud for these types of users.
There are other reasons that alt text is used on websites as well. At first, alt text was used because there were many people using text-only systems such as Linux. While the original reason for alt text is no longer applicable, there are other reasons that this is utilized.
Search engine optimization: Most search engines use alt text to determine the meaning of objects like pictures
Handheld devices: People using handheld devices can take advantage of Internet usage by not waiting for large pictures to load
Low bandwidth: Visitors with low bandwidth can opt to not load graphics and just read the alt text
Utilizing alt text is an excellent search engine optimization technique as well. It can help a website by containing dynamic content that pertains to the keywords used on the website.