Although hard disk drives and flash memory serve the same purpose---they both store computer data---they function in very different ways. Hard drives contain moving parts; flash memory does not.
Hard Drive Storage
Hard drives contain several metallic disks, commonly called "platters," which spin at very fast speeds---most hard drives turn at 7,200 rotations per minute. An actuator arm moves across the platters to read to or write from different areas on the disk, as the computer requires. The actuator stores information onto the spinning platters by magnetizing regions of the disk.
Flash Memory Storage
Flash memory works much differently than hard disk drives. With no moving parts, data is stored in the form of a zero or a one, depending on whether transistors hold an electrical charge. No charge represents a zero; the presence of a charge represents a one. This is how flash memory holds computer files.
Future of Storage
As of 2010, hard disk drives are still the standard storage model for most computers. They hold more data than flash memory and are available at cheaper prices. Smaller types of flash memory, such as USB flash drives and camera memory, are useful for purposes that hard disk drives have a hard time replicating.
Tags: disk drives, hard disk drives, flash memory, charge represents, drives contain, flash memory, Flash Memory
