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A Virtual Private Network creates an encrypted "tunnel" between your device and a VPN server operated by your chosen provider. All of your internet traffic flows through this tunnel, which means your internet service provider, your Wi-Fi router operator, and most websites see the VPN server's IP address rather than your own.
The practical benefits fall into three buckets. First, privacy: your ISP cannot log which websites you visit, and advertisers have a harder time building a profile tied to your real IP. Second, security on public Wi-Fi: coffee shop or airport hotspots are prime targets for man-in-the-middle attacks; a VPN encrypts your traffic before it leaves your device. Third, location flexibility: connecting to a VPN server in another country lets you access region-locked content or services.
Popular consumer VPNs include Mullvad, ProtonVPN, ExpressVPN, and NordVPN. They all work by installing a small app on your device that handles the encryption negotiation automatically. Most support phones, tablets, and desktops from a single subscription.
VPNs are not anonymity silver bullets. Your VPN provider can still see your traffic, so choosing a provider with a verified no-logs policy matters. They also don't block malware or prevent you from handing over your personal details to a website voluntarily.
Free VPNs are almost universally a bad trade — the product is often your browsing data sold to advertisers, which defeats the purpose entirely. A paid VPN typically costs $3–$10 per month.