What is the meaning or mod_rewrite and how to make it enable?
in a simple word:
mod_rewrite is used for rewriting a URL at the server level, giving the user output for that final page.
So, for example, a user requested page
http://www.asite.com/pages/5/, but will really be given
http://www.asite.com/index.php?page=5 by server.
installing and enabling mod_rewrite is server admin responsibility. If you hosted your site in shared hosting, you can not do it. But usually, the hosting already enable it.
To test the mod_rewrite is already installed or no, the easiest way is look at the phpinfo() result.
make a file whatever the name, for example ainfo.php, the content is like this:
<?php
phpinfo();
?>
load that page in your browser, in that case,
www.asite.com/ainfo.phpsearch for text mod_rewrite, usually it located within Apache Handler->Loaded Module Box. Its easier to have Find feature from your browser.
if the mode_rewrite exists, this feature is enabled. if it doesnt, you should contact your hosting provider to ask about it.