Your computer can be set up to share files with other computers on your network, or you may want to turn this ability off if you are going on a public network.
This post has two videos for the price of one: one video that shows how to turn file sharing on and off in Windows, and one for the Mac.
This video on enabling or disabling file sharing is part of a series of quick videos on paperless tips and topics. View more in the series here.
(Photo by FromSandToGlass)