<COLGROUP ...>

<COLGROUP ...> defines a group of columns in the table and allows you to set properties of those columns. <COLGROUP ...> goes immediately after the <TABLE ...> tag and before any <TR ...>, <THEAD ...>, <TBODY ...>, or <TFOOT ...> tags. <COLGROUP ...> works very much like <COL ...>, but be sure to note that <COLGROUP ...> requires both an opening and closing tag.

<COLGROUP ...> is most useful for defining column groups to use in conjunction with <TABLE RULES=GROUPS> to put borders between groups of columns instead of between every column. For example the following code creates a table that puts the first column in a group by itself, all the remaining columns in a group together, and puts borders between the groups of columns.

<TABLE BORDER=1 CELLPADDING=4 RULES=GROUPS FRAME=BOX>

<COLGROUP></COLGROUP>
<COLGROUP SPAN=3></COLGROUP>

See Table Borders: Between Groups of Columns for more details about putting borders between columns.