The Internet Search Sites folder is a special folder, found loose inside the root level of the System Folder, used by Sherlock when it conducts searches involving the Internet. Sherlock places, and refers to, items placed inside this folder as the foundation for its catalogue of Internet search sites (hence the name of this folder). It is extensible; Internet search site documents (Sherlock plugins), with the file extension .src, can be dragged and dropped inside this folder, and they will appear as search sources within Sherlock.