DeleteFile can be passed up to four optional parameters of file types (file types are four letter designators of, you guessed it, the file's type. e. g. "STAK" for stacks, "APPL" for applications, "TEXT" for text files, "PNTG" for paint files, and so on.) If DeleteFile is called without parameters, the Get File dialog will present all types of files, including invisible files (such as the Desktop file). Specifying file types in the parameters will limit the files displayed to the given types. If more than four parameters are supplied only the first four will be used. File types must be enclosed in quotes and must by separated by commas if more than one parameter is used.