Expert Overview:

Dedicated server hardware is also limited to a single tenant usage whereas VPS hardware is shared by multiple hosting customers on one partitioned web server. The latest trends in web hosting have seen companies move beyond the single server model on cloud, VPS, & shared platforms to host multiple copies of a website's files and use network load balancing software to route traffic to the hardware with the most open processing capacity for better response times.
As you can see, a VPS can be the perfect middle ground for many – enough flexibility and resources for those who need more access or control than on a shared server but without the cost of a dedicated server. If you need root access, you can’t get that on a shared server, but you can get it on a VPS. If your site experiences unpredictable swings memory usage, and your host provides it, then the presence of burstable memory will be attractive. And, if you’re a fan of customization, then the fact that you can customize server-level software such as PHP, MySQL, and Apache will perk your interest.  In short, choosing a VPS will allow you to have many of the same characteristics of a dedicated server but in a more affordable and manageable package.