The number specifies the width in em's, pixels or as a fractional value of the table width, as according to the associated units attribute. This approach is more compact than used with most SGML table models and chosen to simplify hand entry. The width attribute allows you to specify the width of the table in pixels, em units or as a percentage of the space between the current left and right margins. To assist with rendering to speech, row and column headers can be given short names using the AXIS attribute. The AXES attribute is used to explicitly specify the row and column names for use with each cell.
Braille limits the width of tables, placing severe limits on column widths.
User agents need to render big cells by moving the content to a note placed before the table. The cell is then rendered as a link to the corresponding note. To assist with formatting tables to paged media, authors can differentiate leading and trailing rows that are to be duplicated when splitting tables across page boundaries. Paged browsers insert footer rows at the bottom of the current page and header rows at the top of the new page, followed by the remaining body rows. The alignment attributes act as defaults for rows overriding the colspec attribute and being in turn overridden by alignment attributes on cell elements.