Define the requirement before the product
Start with application compatibility, CPU and memory demand, storage growth, access requirements and the level of administration your team can provide. Those details are more useful than a product label alone.
Virtual servers: a separate software environment
Cloud, VPS and VDS services use virtualisation to provide separate server environments. Compare the exact resource allocation, storage, access and service terms for each range. Do not assume that different product names guarantee a particular isolation model.
Dedicated servers: the physical machine
A dedicated server rental provides a physical server for your deployment. It can be appropriate when hardware selection, sustained resource use or your own virtualisation environment drives the decision. Review the processor, memory, disk and RAID configuration together.
Colocation: bring your own hardware
If you already own servers, colocation provides a facility environment for them. Your proposal should define rack space, power, connectivity, access and support. Rack rental extends this model to a larger equipment footprint.
Read the network specification carefully
Port speed, committed bandwidth and monthly transfer are different measures. A fast port does not by itself describe the bandwidth included in your service. Compare all of these values and ask how excess use is handled.
Include recovery in the decision
RAID, virtualisation and monitoring do not replace a backup plan. Define what must be backed up, how often, how long copies are kept and how you will test a restore. Agree the operational responsibilities with your provider.