IP - Internet Protocol
Guide by Fudley Pickles (Source: http://tinyurl.com/qjqmb3p)
What is it?
An IP address is assigned to every computer on an Ethernet network. Like the street address for your home, an IP address identifies network computers. It helps traffic flow between computers because each one has its own IP address.
What is it assigned by?
For your home or office network, the IP address is most likely assigned by the router, using something called DHCP. The router keeps track of every computer’s NIC and maps an IP address to the NIC every time the computer joins the network. In the end, all computers have a unique IP address, and the world is safe for local networking.
If the router doesn’t assign an IP address, one must be configured manually.