ESX supports Fibre Channel adapters, which allow a host to connect to a SAN and see storage devices on the SAN.
Fibre Channel Storage depicts virtual machines using Fibre Channel storage.
In this configuration, an ESX host connects to SAN fabric, which consists of Fibre Channel switches and storage arrays, using a Fibre Channel adapter. LUNs from a storage array become available to the host. You can access the LUNs and create a datastore for your storage needs. The datastore uses the VMFS format.