JavaScript: The Definitive Guide, Fourth Edition

The Navigator Object

The Window.navigator property refers to a Navigator object that contains information about the web browser as a whole, such as the version and a list of the data formats it can display. The Navigator object is named after Netscape Navigator, but it is also supported by Internet Explorer. IE also supports clientInformation as a vendor-neutral synonym for navigator. Unfortunately, Netscape and Mozilla do not support this property.

The Navigator object has five main properties that provide version information about the browser that is running:

appName

The simple name of the web browser.

appVersion

The version number and/or other version information for the browser. Note that this should be considered an “internal” version number, since it does not always correspond to the version number displayed to the user. For example, Netscape 6 reports a version number of 5.0, since there never was a Netscape 5 release. Also, IE Versions 4 through 6 all report a version number of 4.0, to indicate compatibility with the baseline functionality of fourth-generation browsers.

userAgent

The string that the browser sends in its USER-AGENT HTTP header. This property typically contains all the information in both appName and appVersion.

appCodeName

The code name of the browser. Netscape uses the code name “Mozilla” as the value of this property. For compatibility, IE does the same thing.

platform

The hardware platform on which the browser is running. This property was ...