Open Virtualization Format (OVF) is an open standard for packaging and distributing virtual appliances or more generally software to be run in virtual machines.
The standard describes an "open, secure, portable, efficient and extensible format for the packaging and distribution of software to be run in virtual machines". The OVF standard is not tied to any particular hypervisor or processor architecture. The unit of packaging and distribution is a so called OVF Package which may contain one or more virtual systems each of which can be deployed to a virtual machine.
For more information, see: