RFC 1942 (rfc1942) - Page 2 of 30

HTML Tables

RFC 1942                      HTML Tables                       May 1996


   *   alignment on designated characters such as "." and ":"
       e.g. aligning a column of numbers on the decimal point

   *   more flexibility in specifying table frames and rules

   *   incremental display for large tables as data is received

   *   the ability to support scrollable tables with fixed headers plus
       better support for breaking tables across pages for printing

   *   optional column based defaults for alignment properties

   In addition, a major goal has been to provide backwards compatibility
   with the widely deployed Netscape implementation of tables. A
   subsidiary goal has been to simplify importing tables conforming to
   the SGML CALS model. The latest draft makes the ALIGN attribute
   compatible with the latest Netscape and Microsoft browsers. Some
   clarifications have been made to the role of the DIR attribute and
   recommended behaviour when absolute and relative column widths are
   mixed.

   A new element COLGROUP has been introduced to allow sets of columns
   be grouped with different width and alignment properties specified by
   one or more COL elements. The semantics of COLGROUP have been
   clarified over previous drafts, and RULES=BASIC replaced by
   RULES=GROUPS.

   The FRAME and RULES attributes have been modified to avoid SGML name
   clashes with each other, and to avoid clashes with the ALIGN and
   VALIGN attributes. These changes were additionally motivated by the
   desire to avoid future problems if this specification is extended to
   allow FRAME and RULES attributes with other table elements.

A Brief Introduction to HTML Tables

   Tables start with an optional caption followed by one or more rows.
   Each row is formed by one or more cells, which are differentiated
   into header and data cells. Cells can be merged across rows and
   columns, and include attributes assisting rendering to speech and
   braille, or for exporting table data into databases. The model
   provides limited support for control over appearence, for example
   horizontal and vertical alignment of cell contents, border styles and
   cell margins. You can further affect this by grouping rows and
   columns together. Tables can contain a wide range of content, such as
   headers, lists, paragraphs, forms, figures, preformatted text and
   even nested tables.





Raggett                       Experimental