JavaScript - Hide a Div at startup (load)?

I have a div in my php page that uses jQuery to hide it once the page has loaded. But is there a way to hide it from...

Changing button text onclick?

When I click on myButton1 button, I want the value to change to Close Curtain from Open Curtain.HTML: <input onc...

Download a File from a URL?

From the title, it's a silly question. But let's say I have a URL, and it's either a SWF, a PNG or an MP3 or someth...