Simplify the following text for a Grade 10 native English-speaking person.
Original: This preserves an old version of the LVâ '' the snapshotâ '' which systems can later reconstruct by overlaying the copy-on-write table atop the current LV .
Simplified: This preserves an old version of the LEâ '' the snapshotâ '' which can later be reconstructed by overlaying the copy-on-write table on the current LE .