Flash Storage vs Hard Drive
Hard drive and the Flash drive are two storage mechanisms used in modern computers. Hard drives, the older device, are still the favorite among the computer users while flash drives are prominent as portable data drives. Solid State drives are also flash storage drives, which are used as the key secondary storage in computers with special requirements.
Hard Disk and Hard Drive
A hard disk drive (HDD) is a secondary data storage device used for storing and retrieving digital information in a computer. Introduced by IBM in 1956, hard disk drive became the dominant secondary storage device for general purpose computers by the early 1960s and still is the dominant form of storage. The technology has improved significantly since its introduction.
The hard drives are prominent due to their capacity and performance. The capacity of the HDD`s vary from one drive to another, but has been consistently increasing over time. Early hard disk drives had very low capacities, but modern personal computers have hard disk drives with capacities in terabytes. The computers used for specific tasks such as data centers have much higher capacity hard drives.
Hard disk drive is an electromechanical device; therefore, there are moving parts inside the disk drive. The hard disk itself is one of the major components of the hard disk drives.
A hard disk drive consists of following components.
1. Logic Board – the controller circuit board of the HDD, it communicates with the processor and controls the relevant components of the HDD drive.
2. Actuator, Voice coil, and Motor Assembly – control and drive the arm holding the sensors that are used to write and read the information.
3. Actuator Arms – long and triangular shaped metal parts with the base being attached to the actuator, it is the main structure supporting the read-write heads.
4. Sliders – fixed to the tip of the actuator arm; carries the read write heads across the disks.
5. Read/Write Heads – write and read the information from the magnetic disks.
6. Spindle and the Spindle Motor – the central assembly of the disks and the motor driving the disks
7. Hard Disks – discussed below
The performance of a hard drive is characterized by the Access Time, Rotational Delay, and Transfer Speed. Access time is the time taken to initiate the actuator by the controller to move the actuator arm with the read/write heads into position over the proper track. Rotational delay is the time the read/write heads must wait before the intended sector/cluster rotates into position. Transfer speed is the data buffer and transfer rate from the hard drive.
Hard drives are connected to the main board using different interfaces. Enhanced Integrated Drive Electronics (EIDE), Small Computer System Interface (SCSI), Serial Attached SCSI (SAS), IEEE 1394 Firewire, and Fibre Channel are the main interfaces used in modern computer systems. Majority of the PC`s use the Enhanced Integrated Drive Electronics (EIDE) that include popular Serial ATA (SATA) and Parallel ATA (PATA) interfaces.
Since Hard Disc Drives are mechanical devices with moving parts inside them, prolonged usage and time cause wear and tear, making the device unusable.
Flash Drive
Flash drive is a computer storage device built using flash memory. Flash memory is a nonvolatile memory technology developed from EEPROM. Flash drives are solid state devices and hence carries numerous advantages over traditional storage drive types.
There are many memory devices built using flash memory technology. However, USB flash drives and the Solid State Drives are the devices comparable to the function of a hard drive. Both USB flash drives and SSD are developed based on the semiconductor technology.
USB flash drive is basically a flash memory chip that can be connected to computer through a USB connector. The flash drives were developed in the mid 1990`s and came to the consumer market at the end of the decade. The devices were a far better alternative to the then portable media such as floppy disks, compact dicks (CD`s), and DVD`s; therefore, became popular very rapidly.
An ordinary flash drive is very light (about 25 grams), small in size, and has a very high capacity. This makes the flash drive the best portable data storage available.
The other type is the SSD`s or Solid Stated Drives. They consist of a bank of flash chips and have very high capacity. They are used instead of the hard drive in computers where speed and lower weight is required. These drives are very light and very fast.
The downside of the SSD`s is the price. Compared to the ordinary HDD, SSD`s may be several time the cost for a gigabyte.
Flash Storage vs Hard Drive
• Hard drives are electromechanical devices, and moving parts are involved in the operation.
• Flash drives are solid state devices, and they are built of semiconductor material.
• Hard drives are less energy efficient, noisy, and slow while flash memory is energy efficient, noiseless, and fast.
• Hard drives are heavy due to their metal covering and components while flash memory devices are very light.
• Hard drives are larger in size and bulky, but flash drives are relatively smaller. (USB flash drives are very small; SSD`s are also small, but depending on the manufacturer need, the size may vary; for example for the SSD`s to be fitted inside a computer chassis the device may need to be enclosed inside a covering that is actually excessive for the device requirements )
• Hard drives are relatively cheap compared to the Solid State Drive on a per gigabyte basis. USB flash drives are cheap.