What is a solid state drive?
A solid-state drive (SSD) which is also known as a solid-state disk is basically a data storage device which uses integrated circuit assemblies as memory to store data for a long time. This drive uses electronic interfaces which is compatible with old block input/output (I/O) hard disk drives which allows simple replacement in common applications.
What distinguishes SSDs from Hard disks is that SSDs have no moving or mechanical components while hard disks have spinning disks and movable heads. SSDs are more resistant to physical shock, do not create noise, have less latency and access time as compared with electromagnetic disk.
Most of the SSDs use NAND-based flash memory, which is capable of retaining data without power. SSDs can also be constructed from Random Access Memory (RAM), for applications which require fast access, but no data persistence after power loss. In such devices, power is employed from separate power sources which can be batteries so that the data can be maintained after power loss.
To understand how SSDs are beneficial over HDDS we need to know how HDDs work. A hard disk stores data in which an actuator arm stretches over the platter and imprints magnetic pulses on the surface by a head, which is used to read the data back.
Pros of solid state drives:
- SSDs have no moving parts: Since they have no moving parts, SSDs use less power as there are no motors to have to draw power from and all of the data is stored in memory chips. On the other hand, HDDs use drive motors to spin up the magnetic platters and drive heads which affects battery life, endurance and temperature. Also the absence of moving parts in SSDs also eliminates the noise and vibration that occurs with HDDs.
- SSDs allows faster data access & start up speed: In SSDs there is no need to spin up the drive platters or move drive heads so the data can be read instantly. A normal SSD boots up in just 15 seconds, while a HDD takes up to one minute to boot up.
- SSDs are tough: While HDDs are not as tough as they are made of sensitive materials which can render a disk unreadable but SSDs can handle extremely hot and cold temperatures quite well and can also withstood shock and force.
However SSDs also have some cons:
- SSDs wear out easily: In Solid state drives, the individual bits can’t be erased and are written to again after a while. Since flash memory has a limited number of times so the data can be written only to one location.
- SSDs are pretty expensive: For a less price you can get much more storage in HDDs but not in SSDs. While a 1TB HDD costs around $50, but at same cost you will get 30GB SSD.
- SSDs have lower storage capacity: SSDs have much less storage capacity as compared to HDDs. As SSDs are not made in high capacities so a user will have to spend extra money for extra storage.
Comparison of Hard Disk Drives and Solid State Drives
|Hard Disk Drives (HDDs)||Solid State Drives (SDDs)|
|Speed||HDD provides higher latency and longer read/write times. It supports few input output operations per second.||SSD provides lower latency and faster read/writes. It supports more input output operations per second.|
|Noise, Electricity and Heat||It uses more electricity to rotate the platters thus generating more heat and noise.||There is no need of rotation so they use less power and do not generate any heat or noise.|
|Defragmentation||The performance of HDDs gets effected by fragmentation so they need to be periodically defragmented.||SSDs are not effected by fragmentation. So defragmentation is not necessary in SSDs.|
|Components||It contains moving parts which are coated with a thin layer of magnetic material. On the top of the disks, read-and-write heads are positioned which are encased in a metal case.||It has no moving parts as it is only a memory chip which is interconnected with integrated circuits along with an interface connector.|
|Weight||They are heavier in weight.||They are light in weight as there is no moving part.|
|Cost||They are not costly.||They are very much expensive.|
Both Hard disk drives and solid state drives has got their own pros and cons. While solid state drives are costly, hard disk drives are cheaper. However SSDs are way more superior to HDDs in term of speed but they are not made in high capacities thus making them much more expensive. Now it depends on the user as which drive he wants to use.
Let us know which drive you will use and why?