How Networks Work
Networks work by devices essentially communicating with one another. An example of a network may be a LAN (Local Area Network) where you will have things such as Desktop PC’s, Laptops, Smartphones, Printers etc communicating with each other in one area such as an office space.
Another example of a network would be a WAN (Wide Area Network) where two completely separate areas, such as two offices in two different countries for example, would connect their LAN’s to one another to form one large network.
What an IP address, subnet and router is
An IP address is a unique set of characters that identifies a device over the internet or a local network. Like a house has a street address, each digital device (PC, laptop, smartphone, printer, camera etc) has an internet number. Over a local network an example of this may be having a laptop on an IP address of 192.168.0.3 for example, another laptop may take the IP address of 192.168.0.4, as it would be the next device on the local network. IP addresses would range from 0 to 255 and can be distributed statically or dynamically. Internet Service Providers (ISPs) would usually assign a dynamic IP to your internet connection, which may change weekly, monthly or yearly in the background.
The benefit of using dynamic IP addresses over static ones are that they can be reused, don't require additional configuration and offer higher security (as hackers cannot know what IP address will be assigned to your servers by the ISP for example).
A subnet is basically the division of a network into several sub-networks all done through IP.
A router is a device that allows a network (and all its devices) to connect to the internet through an Internet Service Provider.
How to create a wired network with a dummy switch
An example of creating a wired network to connect to the internet would be using a switch. You would plug a CAT5/6 cable into one port on the switch and then into a port on a router. This would allow an internet connection to any other device that plugs into the other ports on a switch, using CAT5/6 cables for a wired connection. Any devices connected to the switch would also be able to communicate with one another.