If you’re familiar with web programming and AJAX and PHP, check out this item about Client-side PHP on The Daily WTF. Go ahead, take a look. I’ll wait.
Done? Good. Now, if you’re familiar with what’s happening in that code, I’ll wait while you convulse in horror. :)
Holy expletive, that code makes me angry and want to laugh at the same time. I’ll just reiterate Deane’s headline: Someone please fire the person who wrote that.