By default, all software supports multiple file extensions. iWeb supports at least 5 different file extensions. The basic files that iWeb supports are .SITES. However, not all of the extensions listed on the list are always used to save the effects of work in iWeb. Very often, files with such extensions are used as source data files used by iWeb.
iWeb can be used to convert file formats between the file extensions listed below. You can open a file with one of the file extensions below via iWeb and try to save it in another file format, also supported by iWeb.