Which storage device stores digitally encoded data on rapidly rotating rigid disks with magnetic surfaces and is often internal or portable?

Which storage device stores digitally encoded data on rapidly rotating rigid disks with magnetic surfaces and is often internal or portable?

• A. RAM
• B. CPU
• C. Hard Drive
• D. Power Supply

Answer: (C)

The main idea here is non-volatile storage that uses magnetic surfaces on spinning disks. A hard drive stores data by magnetizing tiny areas on magnetic surfaces that sit on rapidly spinning platters inside the device. A moving read/write head accesses those magnetized areas as the platters rotate, allowing data to be read or written while the system remains powered on or off. This combination of magnetic storage and fast rotation is what makes a hard drive a primary internal or portable storage option. RAM, by contrast, is volatile memory used for quick, temporary data access during operation and loses its contents when power is off. The CPU is the processor that executes instructions, not a storage device. The power supply provides electrical power to the computer but does not store data. The description given—magnetic surfaces on rapidly rotating rigid disks—fits a hard drive best.

The main idea here is non-volatile storage that uses magnetic surfaces on spinning disks. A hard drive stores data by magnetizing tiny areas on magnetic surfaces that sit on rapidly spinning platters inside the device. A moving read/write head accesses those magnetized areas as the platters rotate, allowing data to be read or written while the system remains powered on or off. This combination of magnetic storage and fast rotation is what makes a hard drive a primary internal or portable storage option.

RAM, by contrast, is volatile memory used for quick, temporary data access during operation and loses its contents when power is off. The CPU is the processor that executes instructions, not a storage device. The power supply provides electrical power to the computer but does not store data. The description given—magnetic surfaces on rapidly rotating rigid disks—fits a hard drive best.