ABSTRACT
Most journals require you to use horizontal lines to separate the column headings from the body of the table, and to delineate the top and bottom of the table. It is also permissible to use horizontal lines to separate column headings from subheadings. Within the body of the table, most journals use spaces rather than lines to mark groups of row headings. Most journals do not permit you to use vertical lines within tables, however useful you think they may be.
