Now that we understand a NAS (Network Attached Storage) is a computer with an attached hard drive running Linux as an operating system, the next step is to learn what it does and why it's different than, say, a USB attached hard drive.
The simplest explanation of a NAS is found in the first letter of its acronym. It is a network device. It is connected to other devices over the LAN (Local Area Network). What does this mean? NAS connect through a router.
A router, likely the device in your home providing WIFI, also runs on the Linux operating system. Its purpose in life is that of a traffic cop: deciding where each bit of communication comes from and goes to. It's where the internet comes into your home, your email gets sent to, and all activity of your home network is controlled.
So how is this relevant to us? NAS allow unlimited storage possibilities without regard to physical location. You could have terabytes of storage located in your basement, or if you have fast internet, on the other side of the world; accessible from any computer in the home or office. More practically speaking, NAS permit multiple computers access to the same data, and that is their core strength.
A USB attached drive connect only to a specific computer, but NAS connect to anything capable of speaking to them and it isn't only PCs that carry conversations with NAS.
