So you are programing a VisualForce page and you find yourself needing to hide or show an HTML element on the page. No problem. Here are three simple ways to hide or show one or multiple HTML element just by setting a property on the Controller.
Option 1 - Postback
A real easy way to hide or show an HTML element is to evaluate a Boolean property on the Controller. A lot of folks may not realize it, but you can insert the same formulas you use in Validation Rules, Workflow Rules and so on inside any merge field on the page.