Sometimes your system might crash or a power failure might take the machine down

• Sometimes your system might crash or a power failure might take the machine down
• At the next boot, a lengthy filesystem check using fsck will be done
• fsck will go through the system and try to recover any corrupt files that it finds
• The result of this recovery operation will be placed in this directory
• The files recovered are not likely to be complete or make much sense but there always is a chance that something worthwhile is recovered

/lost+found