Essentially, here’s the criteria I would use to judge things – if your site is made up of primarily static, HTML-based content, then you probably don’t need a VPS package.  However, if you have a large amount of files stored, multiple sites, dynamic content, and the possibility of major traffic from time to time, then you might consider upgrading to a VPS. It’s a powerful package that allows you to do more than you could with a shared hosting plan, but requires less investment than a dedicated server.
Learning how to set up a VPS after upgrading from shared hosting is like leaving the kiddie pool to dive into an Olympic-sized one. You have a lot more room and features to play with, but you’ll need to find your footing before you can start having fun. Now that you know how to configure your VPS, you’ve become acquainted with the command line, which will make it a lot easier to set everything up to your liking.

Let’s start with the difference between shared hosting and VPS hosting.