If you have watched YouTube in recent years, you have almost certainly seen a VPN ad. It promises you will be 'completely anonymous', 'protected from hackers' and 'safe online'. Some promises are true, some exaggerated. To decide whether you need a VPN, it helps to understand what it actually does.
VPN stands for Virtual Private Network. When you turn one on, all traffic from your device first goes, encrypted, to the VPN company's server, and only from there out to the internet. That does two things: whoever is in the middle, such as your internet provider or the operator of a public Wi-Fi network, sees only that you are connected to a VPN, not which sites you visit. And the sites you visit see the VPN server's address, not yours.
What doesn't a VPN do? It does not make you anonymous. If you are signed in to Gmail, Facebook or any other account, the site knows exactly who you are. It does not protect against phishing, viruses or scams: type a password into a fake site and the VPN will not stop it. Most important: it does not make your data disappear but sends it to the VPN company. You are swapping trust in your internet provider for trust in the VPN provider.
When is it useful? When you join a public Wi-Fi network you do not trust, in a cafe, hotel or airport, and want to make eavesdropping harder. When you want to hide from your internet provider which sites you visit. When you are abroad and need a service available only from Israel, or vice versa, subject to the service's terms. And at work, when the company requires a VPN to reach internal systems, which is a different use altogether.
If you decide to buy one, be especially wary of free VPNs. Running servers costs money, and a service that does not charge you may profit from your data, the exact opposite of what you wanted. Choose a well-known provider with a clear privacy policy that has passed external security audits. And remember: for most people, two-step verification, a password manager and software updates protect far more than a VPN.
