An OVF file is a text file that contains information about the packaging and distribution of a software that runs on a virtual machine. It is formatted as per the Open Virtualization Standard Specifications that describes all the requirements (such as security, portability, efficiency and extendibility) for running applications on virtual machines. The International Organization for Standardization (ISO) has adopted OVF as ISO 17203 standard.
Brief History of OVF
OVF file format was introduced by DMTF (Distributed Management Task Force) that creates open manageability standards. It is independent of any particular hypervisor or instruction set architecture. The OVF package contains one or more virtual systems, each of which can be deployed to a virtual machine.
OVF File Format - More Information
An OVF package consists of multiple files placed in a single directory. Among these, it ocntains exactly one OVF descriptor (with extension .ovf) file that is stored in XML file format. It describes the packaged virtual machine information and metadata information about the OVF package such as:
references to the other files in the OVF package, and
Other files that can be found in an OVF package include one or more disk images and optionally certificate files and other auxiliary files.