Technical Terms – A glossary for the world of VPNs

Sist oppdatert: 10/03/2025

This glossary breaks down common VPN terms in plain language. Each term includes a simple definition, why it matters for VPN use, and an example of how it applies to everyday users.

1. VPN (Virtual Private Network)

Definition: A VPN is a service or tool that routes your internet connection through an extra server (location) and encrypts your data in the process. In essence, it creates a private, secure “tunnel” over the public internet between your device and a VPN server.

Significance in VPN use: By using a VPN, your online activities become more secure and private. The VPN server acts as an intermediary: websites and services see the VPN server’s details instead of yours. This means your real IP address and location are hidden, enhancing your privacy and allowing you to bypass local restrictions on content. A VPN is especially useful on untrusted networks (like public Wi-Fi) because it protects your data from eavesdropping.

Example: If you’re on free Wi-Fi at a coffee shop, a VPN will encrypt everything you do online, so others on the same network can’t spy on your passwords or messages. Say you connect through a VPN server in another country – any website you visit will think you’re coming from that server’s location, not the coffee shop. The image below shows a simplified diagram of how a VPN creates a secure tunnel between you and the internet, keeping out hackers and snoops.

2. Encryption (AES)

Definition: Encryption is the process of scrambling data into a secret code so that only someone with the right key can unscramble (read) it. AES (Advanced Encryption Standard) is a widely used encryption cipher in VPNs. For example, AES-256 uses a 256-bit key to lock your data, making it extremely hard for anyone to crack.

Significance in VPN use: Encryption is what makes a VPN secure. When you use a VPN, it encrypts your internet traffic end-to-end. This means even if someone intercepts your data (for instance, on public Wi-Fi or by your Internet Service Provider), all they see is gibberish, not your actual information. Strong encryption standards like AES-256 ensure that your sensitive data – emails, banking logins, credit card numbers – stay private.

Example: Imagine sending a postcard versus sending a sealed letter. Using the internet without a VPN is like a postcard – anyone could read it en route. Using a VPN is like putting your message in a sealed envelope with an unbreakable lock. For instance, when you log into your bank account over a VPN, encryption locks up your credentials, so a hacker on the same network can’t steal your password. This gives personal VPN users peace of mind that their data is safe even on potentially unsafe networks.

3. VPN Protocols (OpenVPN, WireGuard, etc.)

Definition: A VPN protocol is a set of rules that determines how data is formatted, encrypted, and transmitted between your device and the VPN server. Common VPN protocols include OpenVPN (an open-source, highly secure protocol) and WireGuard (a newer protocol known for its speed and strong encryption). Essentially, the protocol is the language your VPN uses to communicate securely.

Significance in VPN use: The choice of VPN protocol affects your connection’s security and performance. Some protocols prioritize top-notch security and reliability (like OpenVPN), while others are designed to be faster or use less battery (like WireGuard). For personal users, this matters because a protocol can influence your VPN’s speed, how well it avoids network blocks, and how safely it keeps your data encrypted. Most VPN apps let you switch protocols in settings, so you can pick one that best suits your activity (streaming, gaming, public hotspot use, etc.).

Example: If you’re streaming videos, you might choose a faster protocol like WireGuard to reduce buffering. For example, a user finds that switching from OpenVPN to WireGuard in their VPN app makes their HD video stream smoother on a home connection. On the other hand, if you’re very privacy-conscious and don’t mind a slight speed drop, you might stick with OpenVPN for its robust security. In practice, most of this happens behind the scenes – the VPN app will automatically use a default protocol (often the best blend of security and speed for general use), so even beginners benefit from these protocols without needing to understand all the technical details.

4. IP Address

Definition: An IP address is a unique number assigned to your device when it connects to the internet, kind of like a digital home address. It identifies your device’s location in the network. For example, your home internet might use an IP like 123.45.67.89. When connected to a VPN, your device is reassigned a new IP address from the VPN server’s location.

Significance in VPN use: Hiding or changing your IP address is one of the main benefits of a VPN. Your IP can reveal your general location and is used by websites to track you or apply regional restrictions. With a VPN, websites and online services see the VPN server’s IP address instead of your real one. This grants you more privacy (observers can’t easily trace activity back to you) and can help avoid targeted ads or price discrimination based on location. It also enables you to geo-spoof your location – appearing as if you’re browsing from another country.

Example: Suppose you live in Germany; your normal IP address will show sites that you’re in Germany. If you connect to a VPN server in the US, you’ll get an American IP address. Then, when you visit a website or online service, it will think you’re in the US. This is how a VPN allows personal users to, say, access a US-only streaming service or see search results as if they are in another region. In everyday use, the VPN makes this switch automatically – you just click “connect” and the VPN handles giving you a new IP.

5. DNS (Domain Name System)

Definition: DNS is often called the internet’s phonebook. It translates the human-friendly addresses you type (like www.example.com) into the numerical IP addresses that computers use to locate servers (e.g., 93.184.216.34). Every time you visit a website, a DNS query is made to find the corresponding IP.

Significance in VPN use: Normally, your DNS queries go through your Internet Service Provider (ISP), which means your ISP can see what websites you’re looking up. A good VPN will route your DNS queries through its own encrypted tunnel as well, or use its own private DNS servers, so no one can sniff that information. This prevents what’s known as a DNS leak – a situation where your browser’s DNS requests accidentally go outside the VPN, potentially revealing the websites you visit to your ISP or others. By handling DNS securely, VPNs ensure that your browsing habits remain private and that you aren’t vulnerable to certain attacks (like DNS spoofing by malicious hotspots).

Example: Imagine you’re using a VPN and visit www.news.com. With a VPN protecting DNS, the query for www.news.com goes through the VPN’s encrypted tunnel to a secure DNS server, so neither the Wi-Fi provider nor your ISP sees what site you requested. If the VPN didn’t do this, your ISP’s DNS could get that query (this is a DNS leak) and know you visited that site, even though the rest of your traffic was encrypted. For personal users, the takeaway is that you should use VPNs that advertise DNS leak protection – it means the VPN is taking care of those website address lookups privately on your behalf.

6. VPN Kill Switch

Definition: A kill switch is a safety feature in many VPN apps that automatically cuts off your device’s internet access if the VPN connection drops. Essentially, if you lose the secure VPN tunnel for any reason, the kill switch “kills” your internet connectivity until the VPN is back up, preventing any unencrypted data from leaking out in the meantime.

Significance in VPN use: VPN connections can occasionally disconnect due to unstable networks, switching between Wi-Fi and mobile data, or server issues. Without a kill switch, if the VPN drops, your device would revert to using the regular internet, exposing your real IP and traffic unintentionally. A kill switch ensures that no traffic leaves your device unprotected if the VPN isn’t active. This is crucial for privacy – it’s like an automatic emergency brake that keeps your identity and data from slipping out when the VPN guard is temporarily down.

Example: You’re downloading a file or streaming on a VPN, and then the VPN server suddenly goes offline. If you have the kill switch enabled, your download/stream will pause because your internet has been cut off entirely – nothing goes out or comes in until the VPN reconnects. This way, your IP and activity aren’t exposed to the network. Many VPN apps let you toggle the kill switch on or off. For instance, on Android devices there’s an “Always-on VPN” setting with “Block connections without VPN”, which is a built-in kill switch.

7. No-Logs Policy

Definition: A no-logs policy is a promise by the VPN provider that it does not keep records of your usage. “Logs” refer to data like the websites you visit, files you download, or even connection timestamps on the VPN. A true no-logs VPN means that apart from minimal necessary information (like your email for account signup or bandwidth usage for network management), the company doesn’t store anything that could link your activity back to you.

Significance in VPN use: Privacy is a main reason people use VPNs. Even though a VPN hides your data from outsiders, the VPN company itself could potentially see or record what you do through their servers. With a no-logs (or zero-logs) policy, the provider is basically saying, “We respect your privacy so much that we choose not to record your activity at all.” This way, even if someone (like a government or law enforcement) asked the VPN for records of a user’s activity, there would be nothing to hand over. It also means if the VPN servers were somehow breached, there wouldn’t be history logs sitting there for hackers to steal. In short, a no-logs policy is key for trust – it ensures your VPN provider isn’t itself a privacy risk.

Example: Let’s say you use a VPN to visit various websites and later there’s a question of whether you accessed a certain site. If the VPN has a strict no-logs policy, they would have no record of that information. There have been real-world examples where VPN providers proved their no-logs claims – for instance, in court cases or external audits, they could not provide user data because none was stored. For a personal user, this means if you choose a VPN with no-logs, your browsing history, timestamps, and original IP address aren’t being saved. It’s like a browser that forgets your history automatically – what you do online stays only with you.

8. Split Tunneling

Definition: Split tunneling is a VPN feature that lets you direct some of your internet traffic through the VPN while other traffic goes through your normal local internet connection. In other words, you “split” which data goes into the encrypted VPN tunnel and which data bypasses it.

Significance in VPN use: This feature is useful for balancing security and convenience. Sometimes you might not want all apps or websites to use the VPN. For example, you may want your international browsing protected by the VPN, but still have local services (like your printer, Smart TV, or local banking site) work directly without the VPN (since some local services might block foreign IPs or perform slowly via VPN). Split tunneling gives you control: you can enjoy VPN protection for specific sensitive tasks or sites, while keeping other traffic (that might be low-risk or needs local access) out of the tunnel. This can also improve speed and reduce bandwidth usage on the VPN for stuff like streaming local content, since not everything is encrypted and routed via the VPN server.

Example: Suppose you’re abroad and using a VPN but you still want to watch YouTube on your smart TV or cast to a device in your home network. With split tunneling, you could set your VPN app so that only your web browser traffic goes through the VPN (perhaps to securely check your email and do online shopping privately), but your YouTube app or casting service goes outside the VPN directly to the internet. Another common scenario: a user enables VPN for their torrent application for privacy, but lets other apps (like a local news app or an online game that works better with low latency) connect directly. This way, split tunneling ensures you’re not overly restricting or slowing down everything – just protecting what needs to be protected.

9. Geo-Blocking

Definition: Geo-blocking is a practice where websites or streaming services restrict access to content based on your geographical location. Essentially, the service checks your IP address to see where you are in the world, and if you’re outside a permitted region, it blocks or changes what you can see. For example, a show might be available on Netflix in the US but “geo-blocked” in Germany, meaning German viewers can’t normally watch it online.

Significance in VPN use: Many people use VPNs to bypass geo-blocking. Since a VPN can give you an IP address from another country, it can trick services into thinking you’re in a region that has access to the content. This is a major perk for personal VPN users who want an open internet experience – you can stream movies, access websites, or use apps that are otherwise unavailable in your actual location. It also helps travelers who want to use services from back home while abroad (for instance, accessing your home country’s news site or banking site which might block foreign connections as a security measure).

Example: If you’re traveling in Europe and go to a site to watch a U.S.-only video, you might get a message, “This video is not available in your country”. This is geo-blocking at work. By connecting to a VPN server in the U.S., you obtain a U.S. IP address and can refresh the site – now the video plays as if you were physically in the U.S. In the image below, a phone is showing a geo-block message on screen (“This video is not available in your country”). A VPN helps avoid this by spoofing your location. For everyday users, it means with a click in your VPN app, you can appear virtually in another country and unlock region-specific content, whether it’s streaming libraries, websites, or even online game servers restricted by region.

10. VPN Server

Definition: A VPN server is a remote computer/server run by the VPN provider that your device connects to when you use the VPN. The server is the other end of the VPN tunnel – it receives your encrypted traffic, decrypts it, and sends it out to the public internet on your behalf (and vice versa for incoming data).

Significance in VPN use: The VPN server you choose determines your virtual location (the IP address you assume) and can impact speed. For example, connecting to a server geographically closer to you often gives better speed, while a server in a specific country will allow you to access that country’s internet content. All your internet data flows through the VPN server, which means the server is essentially masking your IP and handling your requests to websites. A trustworthy VPN server will not keep logs (see No-Logs Policy above) and will be secure, so your data stays protected. In short, VPN servers are the backbone of the VPN service – they are the intermediaries that make your connection private and location-flexible.

Example: When you open your VPN app and select, say, “United Kingdom – London,” you are choosing a VPN server located in London. Your device then connects to that server; from that point on, the websites you visit will think “you” (actually, the VPN server) are in London, and you’ll usually get faster results from UK sites. If you then switch to a server in Japan, your IP changes to a Japanese one and you can, for instance, access a Japanese streaming service as if you are in Japan. For a personal user, using a VPN server is as simple as picking a location from a list. Behind the scenes, the VPN server is doing the heavy lifting – it encrypts and forwards your data and makes sure that when data comes back, it’s encrypted and sent securely to you. This way, you enjoy the internet from that server’s location, with your identity and data protected along the route.