- tgz2vib5.cmd (to convert a TGZ file to a VIB file, formerly included with ESXi-Customizer)
- vib2zip.cmd (to combine one or more VIB files into an Offline Bundle ZIP)
These scripts can be used by Community developers (who provide e.g. drivers for unsupported Whitebox hardware) to package their software into VMware proprietary formats.
Go, read anything you want to know about these tools (and the different formats that they handle), and download them on the project page.