Do not use a table for layout.
Do use a table for data or comparison charts. When working on a table in the Rich Text/HTML editor:
- do not fill anything on the Legacy tab
- identify table headers (number of rows, number of columns)
- set table headers (W3C accessible tables tutorial)
- give the table a caption (this will appear above the table)
- Choose a class (either "table table-bordered" or "table table-striped")