Rule #7: Handle beginning and end tags of a markup element in the same way.

Markup code that requires start and end tags should never be split apart haphazardly.

The HTML tags <body></body>, <head></head>, and <html></html> are always part of the main web page file.
Forms, <form></form>, should always be built in the main web page file. The name should always be unique to the page and static.
If a start tag is in an include, the end tag should also be in one. The names of the includes should be similar and clear, such as <?php include("start_table.inc") ?> and <?php include("end_table.inc") ?>.
If the start tag is dynamically output by a procedure, so should the end tag. The names of the procedures should be similar and clear, such as <script> Template.startTable() </script> and <script> Template.endTable() </script>.