classid (outer object element only, value is always clsid:D27CDB6E-AE6D-11cf-96B8-444553540000)
type (inner object element only, value is always application/x-shockwave-flash)
data (inner object element only, defines the URL of a SWF)
width (both object elements, defines the width of a SWF)
height (both object elements, defines the height of a SWF)
The first argument (String, required) specifies the id used in the markup.
The second argument (String, required) specifies the Flash player version your content is published for. It activates the Flash version detection for a SWF to determine whether to show Flash content or force alternative content by doing a DOM manipulation. While Flash version numbers normally consist of major.minor.release.build, SWFObject only looks at the first 3 numbers, so both "WIN 9,0,18,0" (IE) or "Shockwave Flash 9 r18" (all other browsers) will translate to "9.0.18". If you only want to test for a major version you can omit the minor and release numbers, like "9" instead of "9.0.0".
The third argument (String, optional) can be used to activate Adobe express install and specifies the URL of your express install SWF file. Express install displays a standardized Flash plugin download dialog instead of your Flash content when the required plugin version is not available. A default expressInstall.swf file is packaged with the project. It also contains the corresponding expressInstall.fla and AS files (in the SRC directory) to let you create your own custom express install experience. Please note that express install will only fire once (the first time that it is invoked), that it is only supported by Flash Player 6.0.65 or higher on Win or Mac platforms, and that it requires a minimal SWF size of 310x137px.
The fourth argument (JavaScript function, optional) can be used to define a callback function that is called on both success or failure of creating a Flash plug-in on the page (see API documentation)
