VDS, VPS, OpenVZ, KVM - what's the difference?

Question

OpenVZ

As I understand it, the difference between VDS and VPS is marketing fantasies of salespeople.
The difference between OpenVZ and KVM: KVM cuts resources more strictly and does not allow "overselling".
Run a binary that should respond as quickly as possible over the network - this is better on KVM. Launching a forum site is also possible on OpenVZ.
Is everything right?

Answer 1

OpenVZ is an unsuccessful attempt to make containers, OpenVZ only allows you to run an OS on the same kernel (Linux) and works very poorly with memory.
KVM is a virtual machine that allows you to run any OS and with good resource sharing.
Where containers are needed, there is LXC, where an honest virtual machine is needed, there is KVM.

Answer 2

you wrote a complete
openvz heresy, this is considered a container
if you do everything at your place, then it is logical that the overhead of openvz and lxc is much less than that of the same kvm and it’s easier to run everything on them

Answer 3

See: KVM virtualization is a full-fledged virtual machine (hardware virtualization) with its dedicated RAM, processor core and hard disk. OpenVZ virtualization implies a greater "attachment" to the parent machine (the physical server where the OpenVZ container runs), because all OpenVZ containers running on the same physical machine use a common Linux kernel.
In KVM, resource limits are tighter than in OpenVZ. In OVZ, server performance may deviate up or down, depending on the neighbors, and in KVM, you are allocated a strictly defined amount of resources.
There is no difference between VPS and VDS.
Yes.