Once converted, you cannot convert back to HFS+, so backups are especially important.
Here is what you need to do: BackupĪll Macs that have SSDs drives will have the Mac filesystems converted to APFS. Apple has worked hard to make the transition seamless but there are a few things you can do prior to upgrading. The latest version of macOS, High Sierra, has some major changes for the Mac including a new filesystem, APFS.
