javascript navigator Description

The navigator object in many ways represents the browser application. As such, the browser is outside the scope of the document object model. Even so, the navigator object plays an important role in scripting, because it allows scripts to see what browser and browser version is running the script. In addition to several key properties that both Navigator and Internet Explorer have in common, each browser also extends the property listing of this object in ways that would generally benefit all browsers. IE duplicates this object under the clientInformation object name, but for cross-browser compatibility, you can use the navigator object reference in all browsers.