About WebArchive Extractor
WebArchive files can be created by saving a web page in Safari (saving all the graphics, css, and images) or you can create one with TextEdit.

This utility’s focus is on helping you to create simple HTML pages with images using TextEdit. For example, after you create a document with images in TextEdit, you can save the file as WebArchive, use this utility to convert the file into a directory structure, and then upload the extracted directory structure to a web server. This process can be used to create help files for web applications or very simple web sites.