It will download the last version of every file present on Wayback Machine to `websites/example.com/`. It will also re-create a directory structure and auto-create `index.html` pages to work seamlessly with Apache and Nginx. All files downloaded are the original ones and not Wayback Machine rewritten versions. This way, URLs and links structure are the same than before.
You may want to supply a specific timestamp to lock your backup to an older version of the website, which can be found using the Wayback link: http://web.archive.org/web/20060716231334/http://example.com