The lost+found directory (not Lost+Found) is a construct used by fsck when there is damage to the filesystem (not to the hardware device, but to the fs). Files that would normally be lost because of directory corruption would be linked in that filesystem's lost+found directory by inode number. Some of these might be lost directories or lost files or even lost devices. Each filesystem should have its own lost+found directory, but you might be looking at a system with only one filesystem. In general, you should hope that the directory is empty; but if there is corruption, be thankful that in many conditions files can be recovered after fsck places them here.

The lost+found directory (not Lost+Found) is a construct used by fsck when there is damage to the filesystem (not to the hardware device, but to the fs). Files that would normally be lost because of directory corruption would be linked in that filesystem's lost+found directory by inode number. Some of these might be lost directories or lost files or even lost devices. Each filesystem should have its own lost+found directory, but you might be looking at a system with only one filesystem. In general, you should hope that the directory is empty; but if there is corruption, be thankful that in many conditions files can be recovered after fsck places them here.