How does a screen reader read a web page, form, or a table?
In most cases, screen readers speak all page elements in the same order as they appear in the document’s source code, left to right and top to bottom. If you are not using a screen reader, you can usually use the mouse to see the reading order. When you click and drag, the order in which text, table cells, and images are highlighted is the order in which a screen reader will read them. Another good option is to use a text-only browser, such as lynx to preview your pages.