A VPN is a means of creating secure communications over a public network setup. VPNs such as LimeVPN use encryption and authentication to make sure information is kept private and confidential. Therefore, you can share data as well as resources among various locations anonymously without your data being compromised.
It is a virtual point-to-point link, which is determined by traffic encryption, virtual tunneling protocols or dedicated connections. This description can also be used to define what is a VPN.
VPN vs. Proxies
The common aim of a proxy and a VPN is to hide your IP address i.e. your identity and browse the web anonymously and securely. However, you could say that with a proxy you are anonymous and with a VPN you are secure.
When it comes to cost, proxies provide better anonymity and speed at an affordable price.