Known as virtual private network, you can think of it as an encrypted connection where no one gets to know or sniff out the data you're sending to the receiver. The route through which the data travels is secure and encrypted. Upon logging in, you'll essentially be connected to your vpn provider's server and all of the data will be going through that route. even your ISP won't be able to discover anything other than the fact you're using a vpn. so that kind of makes you totaly safe from everyone, including the hackers lurking in public spots and the authorities that spy on their citizens.
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