hard drive

US /ˈhɑːrd draɪv/
UK /ˈhɑːrd draɪv/
"hard drive" picture
1.

a high-capacity, self-contained data storage device containing a read-write mechanism and one or more platters, used in computers.

:
I need to replace the hard drive in my old laptop.
Make sure to back up your data to an external hard drive.