Solid-State Drive

File Format
Name	Solid-State Drive
Ontology	Physical File Formats Flash memory Solid-State Drive

Solid-State Drive (SSD) is a type of flash memory that is commonly used to replace hard disk due to various design constraints that makes it a suitable storage medium. Constraints such as (but are not limited to):

• Performance factor, SSD has no moving parts enabling faster seek times, higher data throughput,
• Power consumption, conventional hard disks draws a significant amount of power at start-up, in order to spin the platters for instance, SSD does not have these components, thereby eliminating the initial power draw requirements,
• Noise considerations, unlike hard disks, SSD does not make any noise when it is in operation,
• Lower-profile integrations, many modern thin laptops often come with SSD, without a casing unlike hard disk, therefore making it as thick as a few credit cards stacked on top of each other,
• Exposure to external vibration are unacceptable, where hard disks being mechanical, cannot tolerate excessive external vibrations while it is in operation, as this may cause the head inside the drive to jump on the rotating platter, or forcing itself to park,
• Durability, especially against cheaper USB flash drive which typically has less finite write/erase cycles,
• Weight impact, SSD is also available as disk-on-a-module (DOM), whereas it is almost impossible to find an equivalent hard disk counterpart,
• Submerged in non-conductive liquid. In applications where air cooling is not allowed, it is possible to submerge SSD in non-conductive liquid, most or older hard disks have a breather hole, which when submerged, adds friction to the spinning platter and increases wear to the motor for instance.

However, SSD is not without its flaws, such as:

• Cost, especially the "$/GB" comparison against conventional hard disks at significant storage capacities,
• Longevity of data where it is exposed to environments that performs excessive write/erase cycles in some extreme cases,
• Inability to "hear" if SSD is dying/dead, mechanical hard disks generally makes audible noises when running normally, and in a quiet environment, it is possible for a trained ear to tell if a hard disk is dying or dead. SSD does not make any noises regardless if it is functioning normally or dead,
• "Percussive maintenance" is not possible with SSD, as they do not physically have a head like conventional hard disks, which may become "unstuck" if one physically hits the device with their bare hands. Data recovery such as the old "freezer trick" also does not apply to SSD.

SSD, unlike hard disk, can come with various connectors, such as SATA, NVMe, PCIe, whereas hard disk was designed generally to use the likes of (ribbon/flexible flat) cables (e.g. Parallel ATA/Serial ATA), with the exception of hardcard for instance, which used ISA slot, and had capacities ranging in megabytes (MB), or using backplane(s).

Links

• Solid-state drive on Wikipedia