An icon is an object that adheres to the Icon interface. The second argument provides a description of the icon, to be used by assistive technologies . This description might be used, for example, to help a visually impaired user understand what information the icon conveys.
Applets generally load image data from the computer that served up the applet.
There are two reasons for this. First, untrusted applets can't read from the file system on which they're running. Second, it just makes sense to put an applet's class and data files together on the server. If you're writing an applet, you might want to copy the getURL method for use in your applet. For more information on specifying the source of image data, see Specifying the Image Source .