What is Chrome?
Chrome is the user interface parts of the application window that are outside of a window's content area.
Toolbars, menu bars, progress bars, and window title bars are all examples of elements that are typically part of the chrome.
What do you do with Chrome
Here are the following examples of what you can do with Chrome:
Resources
[Configurable Chrome | http://www.mozilla.org/xpfe/ConfigChromeSpec.html] by Benjamin Smedberg <benjamin@smedbergs.us>