The following browser detection properties are available to all scripts:
The pui.is_XX flags are Boolean type, and will always be defined. They will be set to true or false, as appropriate. The values pui.ie_version and pui.ie_mode are Number type values which are defined only when pui.is_ie is true. pui.ie_version gives the actual version number of Internet Explorer, and pui.ie_mode gives the Internet Explorer rendering mode. In most situations requiring browser detection, pui.ie_mode is the relevant value.
See here for a discussion on browser detection.
Note: Support for IE8 and and IE9 have been dropped in Profound UI Version 6 Fix Pack 0.4.