Shared and VPS hosting have some things in common. It is important to understand the difference between the two to choos an appropriate solution that most suits your website requirements.
First of all let us take an overview of Shared Hosting and VPS Hosting.
Shared Web Hosting : Shared Web Hosting is the most basic type of web hosting solution. Shared hosting packages are cheap and affordable in terms of pricing. This type of hosting is more preferred by small websites that require less resources. In this, a physical server is shared by multiple users and websites. This being affordable, is more preferred by users as the cost of the server and its resources are shared by multiple users. Shared web hosting can sometimes not suit all types of websites, as different websites require different amounts of resources such as bandwidth and disk space. There may be websites that receive high traffic, hence consume bandwidth that is greater than what is offered with a shared hosting package. In such cases one needs to opt for a higher plan such as VPS Hosting or a Dedicated Server Hosting plan.
To start with, you may choose a Shared Web Hosting package and later upgrade to a VPS or Dedicated hosting plan as per the requirements of your website/s. Many webhosting providers offer flexible upgrade options and you can switch from one plan to another with less waste of efforts, keeping the website up and running over the web without any downtime.
The only drawback of shared hosting is that you do not get much privileges with it.
VPS Hosting or Virtual Private Server Hosting: A VPS is the next option to Shared Hosting in terms of resources and privileges. Basically, VPS shares a similar concept with Shared Hosting, but there is are few major differences between the two i.e. resources and privileges. 
Similar to a shared plan, multiple VPS accounts are created on a physical server using a virtualization technology. With a VPS you get better resources such as bandwidth and diskspace and you have better control over the server. You get complete admin access to the server, which means you can create, modify, delete ,install or uninstall applications of your choice, which is not possible on a shared server. VPS hosting plans too are affordable. With it you get to experience a dedicated like environment. The only difference is the resources and price. Each client using a virtual server is given a fixed share of a server.
A VPS is more preferred than shared hosting or Dedicated server hosting plan. The reason because, shared hosting packages offer less resources, security and privileges whereas a dedicated server is more expensive and the resources available with it are sometimes much more than what is required. On a VPS there not much restrictions set which isn’t the case with a shared hosting server plus you have almost similar privileges as that of a dedicated server. As said earlier with a shared hosting plan you do not have much privileges whereas with a VPS hosting plan, you get complete root or administrator access of the server. You have the privilege to configure your own applications and softwares.
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