It can increase the speed to write and read your data to your hard drives and it can make backup copies of your hard drives so that if one hard drive crashes, you can most likely retrieve all your data.
(It; can increase; the speed to write and read your data to your hard drives) (it; can make; backup copies of your hard drives) (you; can most likely retrieve; all your data)
It it you
can increase can make can most likely retrieve
the speed to write and read your data to your hard drives
backup copies of your hard drives
all your data