How is an IP Packet moved around the internet

Unlike a shipping package which can be moved around by a person or a shipping truck, An IP Packet is so dumped. It needs a device that can put and wrap it in a Layer-2 box then send it to another device.

Any devices (server, firewall, PCs, modem ...) that have the ability of receive an IP Packet, read its Header IP information then forward to the next device are called routers. Routers rely on its routing table to forward a received IP packet.

What is IP address

Because all the network devices are using the same TCP/IP protocol to communicate to each other. They must have a unique address to distinguish from the other. That address is called IP address.

Now we have two version of the IP addresses: IP version 4 (IPv4) and IP version 6 (IPv6). Although IPv4 is supposed to end soon because it supports only 2^32 = 4.3 billion addresses, it is still widely used until now because of the NAT.

The Network Address Translation allows us to use any Private IP addresses and translate them into Public IP Address(es) in order to communicate to the internet (Public IP Addresses).

Basic knowledge of the TCP/IP Protocol suite

People need some things in commons so they can talk together. So does the computers. They all need to use the same protocol in order to maintain an efficiency communication.

You could build up your own style of network protocol but if you would like to communicate with billion devices out there, you have no choices. The TCP/IP protocol is used right now on almost all network devices. It based on the OSI model.