VPN (Virtual Private Network) secures and anonymizes connection between your device (laptop, mobile phone, TV) and an online server (website, Netflix app, Google search) you are connecting to.
Typically VPN service is provided in form of application which you install on your computer/device and use everytime you are going online. Most of the VPN applications are paid (typically around $9.99 per month), but there are also some free ones.
Connecting to the VPN server you are making yourself hidden – your real IP address and physical location are masked behind the vendor’s server, so no one can track you. Especially hackers, governments, or big companies.
It also enhances your security as the whole connection is encrypted, so no one can steal your personal information or see what you are doing. This very useful on public Wi-Fis (cafes, airports).