What `the_content` goes through
the_content is one of the most known WordPress template tags. It wraps itself around the get_the_content tag (a little lower in the source) and applies the the_content filter to it.
the_content filter applies at least 10 default filter functions to the content before displaying it. WordPress post content is usually just altered here and there, not too drastically (except shortcodes, of course), and sometimes you just have to know what to expect when displaying filtered content.

