Section 508 Web Standards
(g) Row and column headers shall be identified for data tables.
What does it mean?
Cells that are row and column headers in a data table will be identified using special attributes to avoid confusion when screen readers are reading the content.
How to evaluate
The screen reader appropriately identifies row and column headers, and data is read in a logical order. Data cells should take up one row so older screen readers can read the content. The table does not contain spanned rows or columns. The TH (instead of TD) and scope attributes are used to define each header. Most browsers display text in bold face and center it when the TH tag is used. Other attributes are used such as Caption to display a title above the table and Summary to explain the results of the table. Tables used solely for layout do not need special identification of cells like the data tables.
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