In Drupal, users can accidentally lose content on node add/edit forms by clicking the "More information about formatting options" link and browsing to a new page. That's not so good.

I remember when I first started working with Drupal, one of the biggest challenges when theming was discovering what variables were available to me.

Perhaps I didn't like the formatting of the date as supplied by the default $submitted variable and wanted to see if there was a simple timestamp I could format...?

Luckily I came to learn of the get_defined_vars() PHP function which returns an array of all defined variables within the current scope.