What is a VPN?

What a VPN actually changes

When you connect through a VPN, two things change. Your traffic travels inside an encrypted tunnel between your device and the VPN server, so anyone watching the network in between — the café Wi-Fi, the hotel router, your ISP — sees only that a tunnel exists, not what is inside it. And the sites you visit see the VPN server's IP address instead of yours.

That is genuinely useful. It is also narrower than most marketing suggests.

What a VPN does not do

• It does not make you anonymous. Log into an account and you have identified yourself regardless of which IP you arrived from.
• It does not stop browser fingerprinting. Your screen size, time zone, fonts and GPU are unchanged, and a mismatch between a VPN's country and your reported time zone is itself revealing.
• It does not block malware or phishing. An encrypted tunnel to a fraudulent site is still a connection to a fraudulent site.
• It does not remove cookies or the tracking already tied to your accounts.
• It does not always hide your real IP. WebRTC can bypass the tunnel entirely — worth testing rather than assuming.

You are moving trust, not eliminating it

Without a VPN, your ISP can see which sites you connect to. With one, it cannot — but the VPN provider can. You have not removed the observer; you have chosen a different one.

That makes the provider's logging policy the most important thing about it, and far more important than server counts or connection speed. Look for a clearly written no-logs policy, an independent audit that actually tested it, a jurisdiction you are comfortable with, and a transparency report. Be wary of free VPNs in particular: running server infrastructure costs money, and if you are not paying, the traffic itself is often the product.

When a VPN is genuinely worth using

• Public Wi-Fi. The original use case, and still the strongest. On a network you do not control, an encrypted tunnel is meaningful protection.
• Networks that monitor or filter. Hotels, airports and some workplace guest networks log more than you would expect.
• Keeping browsing from your ISP. A reasonable preference, provided you trust the VPN more than the ISP.
• Region-locked content. It works, though many services actively detect and block VPN ranges.

The cost side

Your traffic takes a longer route, so latency rises — roughly the round trip to wherever the server sits. Throughput usually drops somewhat from encryption overhead and server load. Some sites will show more CAPTCHAs, because shared VPN addresses attract abuse. None of this is a reason not to use one; it is a reason to choose a nearby server when latency matters.

Frequently asked questions

Does a VPN make me anonymous?

No. It hides your IP address from the sites you visit and encrypts traffic to the VPN server, but it does not prevent browser fingerprinting, remove cookies, or stop you being identified when you log into an account.

Is a free VPN safe to use?

Treat free VPNs with caution. Running server infrastructure is expensive, and providers that do not charge often monetise user traffic instead. A VPN sees everything your ISP would have seen, so the provider's business model matters.

Does a VPN slow down my internet?

Usually somewhat. Traffic travels further and must be encrypted and decrypted, which increases latency and can reduce throughput. Choosing a server geographically close to you keeps the impact small.

Can my real IP address leak while a VPN is connected?

Yes. WebRTC can query your operating system directly and bypass the VPN tunnel, exposing your real address to any site you visit. Testing for this rather than assuming it is handled is worthwhile.

Does a VPN protect me from viruses and phishing?

No. A VPN secures the connection, not the content. An encrypted tunnel to a malicious website still delivers the malicious website. Antivirus software and careful link checking cover different risks.