Editing File system (section)

====In-place conversion====
In some cases conversion can be done in-place, although migrating the file system is more conservative, as it involves a creating a copy of the data and is recommended.<ref name="ms">{{cite web|url=https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-xp/bb456984(v=technet.10)|title=How to Convert FAT Disks to NTFS|website=[[Microsoft Docs]]}}</ref> On Windows, FAT and FAT32 file systems can be converted to NTFS via the convert.exe utility, but not the reverse.<ref name="ms" /> On Linux, ext2 can be converted to ext3 (and converted back), and ext3 can be converted to ext4 (but not back),<ref>{{cite web|url=https://ext4.wiki.kernel.org/index.php/Ext4_Howto#Converting_an_ext3_filesystem_to_ext4|title=Ext4 Howto|work=kernel.org|access-date=29 April 2016}}</ref> and both ext3 and ext4 can be converted to [[btrfs]], and converted back until the undo information is deleted.<ref name="btrfs">{{cite web|url=https://btrfs.wiki.kernel.org/index.php/Conversion_from_Ext3|title=Conversion from Ext3|website=Btrfs wiki}}</ref> These conversions are possible due to using the same format for the file data itself, and relocating the metadata into empty space, in some cases using [[sparse file]] support.<ref name="btrfs" />