What are IP addresses and how do they work?

If a computer is on a network, it has an IP address – If you do not have an IP address, you can not access a network, and you can not access, for example, the Internet.

Initially, the IP address is assigned completely automatically every time you start your computer, and most people never need to give the IP address the least thought.

A traditional IP address consists of four sets of numbers, each consisting of between one and three digits. Each number is separated by the sentence. Each and every computer and device on the internet basically has their very own IP address. The address is used, for example, to identify a computer on the Internet, and some websites also store information about your IP address.

IP stands for Internet Protocol, and an IP address can in some ways be compared to a phone number used when computers on the Internet communicate with each other. So, the Internet will hit your IP address so that it knows where to send it.

When should I know my IP address?

To play games or otherwise connect two computers over the internet, you must know the IP address at least on one computer. You can always view your IP address at this site “what is my ip address“. However, be aware that many games and applications require you to open a port in your router before you can use the application over the web.

Every single IP address that links a user or device directly to the Internet is unique. However, your network also consists of “local network” which ensures the connection between your computers, devices and the router internally.

You can compare it sort of like your router is a post office that consists of a large network on the internet with each router being a post office sending and receiving packets (data). Completely independent of this, it distributes messages from the Internet to the individual computers, phones, TVs, and anything else you’ve connected online.

Each router thus initially manages a local network, and here are other IP addresses that typically resemble each other – which makes it easier to set up networks.

For example, a routers ip will often be or on the local network and an IP on a computer in a local network will often be These addresses, however, will never be directly connected to the Internet as they are reserved for local networks.

But there are also fixed patterns among the IP addresses of the network, and these regular patterns are one of the reasons why some websites occasionally find that you are from Denmark even if you visit an international website. The IP address can also tell who your ISP is.

New IP system

In the future, the IP addresses will look different. The above system is based on IPv4, but you will continue to switch to IPv6 in the future – in practice, it will only have very little significance for you as a user, but it means that your IP may rarely look different.

The reason for switching is simply to run out of IP addresses.

Yet there is not much reason in practice for ordinary users to get an IPv6 address, and when there is a need, you will automatically be assigned one from your ISP.