Let me write from my experience. I started working on VMware ESXi in 2005. This was the my first experience towards concept of virtualization. There was always a discussion, that virtualization will help us to move towards cloud computing, I thought how??
We used to create datacenter where each server was running hypervisor, and create multiple vms into it. That was the limit. How can I make it accessible that environment as a service to others. When I say Service it means through web. It is not possible for everyone to install hypervisor and create vms. Even, they can do , getting each feature is very costly.
So the big player mainly amazon came with the concept. They have large number of servers [compute],storage,networking devices in a datacenter. All the servers running hypervisor and managed by any centralized access point. Now its comes to make it accessible to everyone as a service [Through Web]. I can place the order, that i need a vm. As a developer, or product owner I don’t need to worry about Datacenter, environment etc.
As a end user, I just need one OS platform where i can configure the stuff. From the web, how someone place a market order or a book order, can place a os order. It make it feasible to access remotely through internet. That is a cloud computing.
Same way Google also came up with the platform called GCP [Google Cloud platform]. Same like other providers It also provides instances [vms] through web. It can have different hypervisor, hardware etc. For end user while placing the order below are the basics.
-Compute,storage and networking: These are the basic need.