The tbody, tfoot, and thead objects reflect the tbody, tfoot, and thead elements, respectively. For scripting purposes, you can treat each of these as a container of row groups inside a table. They all share the same properties and methods, so you need to keep their HTML functionality straight as you script these elements. A table can have only one tfoot and one thead element, but multiple tbody elements. Also, by default, Internet Explorer 4 or later and Netscape 6 create a tbody object for every table even if you don't include one in your table's source code. This default tbody element encompasses all rows of the table (except those you have wrapped inside thead or tfoot elements, if any). Although these objects are implemented in IE 4 for the Macintosh, they are incomplete. Moreover, the row insertion operations noted in the table element are just as strange for these objects under IE 4 for the Mac.