This article explains how to install VMware ESXi in a virtual machine. Installing ESXi in a virtual machine provides a way to try the product without dedicating hardware to it. A virtual ESXi machine may be useful if you are studying to become a VCP (VMware Certified Professional).
By default, you can only run 32-bit virtual machines in ESXi. If you need to run 64-bit virtual machines, see the Additional Information section in this article.