Off-Screen Model

A data structure maintained by screen readers that represents the content and structure of the visual display in a form that can be navigated non-visually. Traditional screen readers intercept system calls to build this off-screen model because they did not have direct access to the Document Object Model of web pages. The off-screen model enables features like virtual cursor navigation, find functionality, and structural browsing by headings and landmarks. A limitation is that off-screen models can become stale when web page content changes dynamically, which is why modern screen readers increasingly use direct DOM access and accessibility APIs instead.