There are too many confusing VMware products from VMware but lack of clear descriptions about them. For example, it is hard to know what difference or what relationship between vSphere Hypervisor and VMware player. I searched multiple days about these two concepts through Google, but I still did not clear idea about their relationship, and there is no any information about them in VMware official site ether.
What I can do it I try to record something which I have gotten by now, through internet.
From old information people called vSphere was actually a product name, it included multiple products such as VMware ESXi, vCenter, vSphere Client.
From new concept, vSphere is VMware’s cloud computing virtualization platform.
The biggest competitor to vSphere is Microsoft's Hyper-V.
It is one product with the vSphere software bundle shipped, it is VMware’s Hypervisor OS, can be installed on a bare-metal without any other OS, just like you install Windows OS on a computer. after you installed ESXi, you can create some VM instance on it;
It is just VMWare ESXi’s new name.
vSphere compared with Microsoft’s Hyper-V Server.
It is a simplified version of VMware workstation. The newer version of VMware player can create VM instance, but old versions could not.
What I think is VMware Player might be like Microsoft’s Virtual PC ? A simple virtualization tool.