.htaccess is more than file extension that manages Web Server configurations. Here are some useful tips that can really make your life quite easy on Apache.
Apache: Useful .htaccess tips & tricks
Apache2- Enabling SSI for HTMLs using .htaccess
See how to enable server side include (SSI ) on Apache2 for html file types (like .html, .htm, .shtml) using htaccess configuration. This can really remove redundancy of your code and make it more maintainable.