Shared hosting enables thousands of people to get their own sites hosted at a very reasonable fee. There are a few disadvantages, though. Due to the fact that hundreds of sites can be hosted on a single server, resources such as CPU, disk space, and bandwidth have to therefore be shared with your virtual neighbours.
Shared resources are usually not problematic for small to medium sized sites. Your main limitation will be the lack of control over system level software – http servers, mail servers etc. You aren’t given any choice in operating system and you also cannot compile programs or undertake administrative tasks such as setting up Spam filters or firewalls.

Many people would just not be interested by this, and it is true that the most website owners are not able or interested to handle this kind of work feeling happier to leave it to the hosting company. Those who would like to gain better control over their server environment or wish to experiment with new software, however, can access this level of management with a Virtual Private Server.

A virtual private server (VPS) is a physical server that has been segmented (with software) into several virtual machines, each acting as an independent dedicated server. The physical resources such as RAM, CPU and disk space will also be shared, but each VPS will operate independently of the others. Each VPS can have a different operating system and can be arranged in any way possible.

The strategic advantage of VPS is that it will allow each VPS administrator access to the root level of his virtual server. This kind of access will allow the administrator to install and delete software, set permissions, create accounts – and altogether, do everything that the administrator of a ‘real’ sever can.
Along with providing more control over your hosting environment, a VPS is more secure than shared hosting. On a shared server all websites have the same operating system, so if an intruder were to find access to the root of the server, he could destroy any or all of the websites on that server. A VPS, however, is divided in such a way that even if a hacker were to gain entry through one account, he wouldn’t be able to access the others. There is no way to set up root level access from one VPS to another, as each VPS is invisible to the

Virtual Private Servers can be set up in many different ways so make sure you understand how the hosting company has allocated its resources. The most common configuration is to divide all the physical resources evenly according to its number of accounts. In so doing, if there are 10 virtual servers, each server would receive 10% of the total bandwidth, CPU, memory and disk space.
The disadvantages of VPS almost even out with the advantages. The control that a VPS account can provide can be dangerous if you aren’t sure of your actions. You can delete files, set permissions improperly, allow virus-laden software on the system and, in general, really mess everything up. If you don’t have sufficient knowledge to administer a server, or aren’t willing to learn, VPS won’t be for you.
However, if your website has outgrown shared hosting, VPS will offer a cost-effective alternative to dedicated hosting. When you shop for a VPS host, make sure you find out how system resources are divided up, the number of VPS accounts on each physical server, the method for upgrading, and the choices of the operating systems.