Enhancing the Accessibility of SharePoint

“Visually impaired users rely on alternative text for a description of what an image conveys. Using alternative text, you can provide a text description that conveys the same information as the information you are trying to communicate through the image that the text is associated with.

You can customize the alternative text displayed for images by setting the alt attribute of the appropriate <IMG> tag in SharePoint ASPX user pages such as the Home page or list view pages. For example, you can set the alternative text used for the Home logo and other images contained within these pages by modifying the respective Default.aspx or AllItems.aspx page. Alternative text for logos can be customized within the following ASPX pages of a site definition:

• Default.aspx. The Home page.
• AllItems.aspx. The page for viewing all the items in a list.
• NewForm.aspx. The page for creating a list item.
• EditForm.aspx. The page for editing the contents of a list item.
• DisplayForm.aspx. The page for viewing a list item.
• Site application pages in the Local_Drive
:\Program Files\Common Files\Microsoft Shared\web server extensions\60\TEMPLATE\LAYOUTS\Locale_ID directory. For a list of possible values for Locale_ID, see LCID Property.

When you create a site definition, as described in Creating a Site Definition from an Existing Site Definition, the new site definition directory includes one Default.aspx file, as well as AllItems.aspx, NewForm.aspx, EditForm.aspx, and DisplayForm.aspx files for each list type (for example, announcements, tasks, document libraries, and so on). Each list you create in turn creates an instance of one of the list types, whose supporting XML, ASPX, and other files reside in one of the subfolders of the Local_Drive”

Read the full article at Microsoft’s own Developer Network.