Share is a webserver that can share files. When you close the window, the sharing stops. It shares files in the current directory. It shares the files from one directory level down if the particular directory contains the file 'pwd.txt'; in this case it requires a password. This file needs to contain a list of 'username:password' combinations (withouth the apostrophes). It does not do encryption, so anybody listening on the network will see all the things that get transferred, including the passwords and protected files.