myVM.vmdk (descriptor – text) myVM-flat.vmdk (actual disk data – binary) Deleting or altering a flat file will corrupt the associated virtual machine. Always manage disks through vSphere or VMware tools.

In VMware virtualization, a "flat file" typically refers to the file, which is the raw disk data file for a virtual machine (VM). Unlike the descriptive .vmdk file (a small text header), the flat file contains the actual binary data written to the virtual disk.