Virtual means that the server runs in a virtualized environment, a cloud server rather than a physical server. This differentiates Virtual Private Servers from dedicated servers, which are physical machines in a data center rack. Virtual servers have the same functionality as a dedicated server and they look more or less the same from the client’s perspective, except that several virtual servers live on a single physical server.
VPS can be a perfect solution for businesses that want many of the features of a dedicated server but don't have the resources to physically host, support and maintain the server hardware. A shared environment won't offer you the same bandwidth or Web hosting space that a VPS will be able to support and there are also many more constraints on the software you can run in a shared hosting environment. In contrast, a VPS will give you the freedom to install, delete, reboot and do all the functions as if you have your own server. You also get an increased level of security as each VPS is isolated and completely separate from other Virtual Private Servers on the same physical server. The environment is secure and protected and each VPS can be rebooted or stopped independently – even if a hacker infiltrates one VPS there is no access to the others using the same physical server.
If you'd like to run a VPS, I'd suggest you to look for a managed one with cPanel. cPanel is a piece of software that facilitates a lot configuring the server, while managed means that the support guys will help you with initial configuration of the server, and also help you out with config/upgrades whenever you need help. It's a bit more expensive than non-managed, but if you don't know how to manage/administer a server, than it's essential. You can find a decent managed VPS in USA from 20 $ and up.
Virtual Private Server (VPS) hosting definitely seems to be the future of the web hosting world. An unmanaged VPS hosting service is a solution that is completely under the control of the customer. Web hosting providers do not recommend such a service to people who don't know how to establish, manage, and function a web server; in such a case, managed VPS hosting provides a better solution.