HDD vs SSD

HDD (Hard Disk Drive) vs SSD (Solid State Drive)

HDD is an old drive technology which uses a magnetic platter, a magnetic arm (write/read head) and an electric motor. Data are written in a magnetic way on the platter. SSD is a non-volatile flash memory (NAND) without moving parts. Next, the main advantages/disadvantages of both technologies will be mentioned.

Cost

The cost of HDD is low compared to that of SSD since the latter technology is more modern and it involves a flash memory.

Speed

The read/write speed of SSD is several times higher than that of HDD and this fact is attributed to the lack of moving parts and use of NAND flash memories (electric circuits).

Power consumption

The power consumption of SSD is 2-3 Watts while a typical power consumption of HDD is 6-7 Watts.

Noise

There is no noise produced by SSDs due to lack of moving parts

Heat

Less heat is produced by SSDs due to lack of moving parts and low power consumption.

Durability

A SSD is more durable than a HDD since is less sensitive to vibration, crash etc. It is also safe from external magnetic influence.

Fragmentation

HDD are sensitive to fragmentation since large files can be scattered along the platter and defragmentation is necessary to decrease read time. SSDs are not sensitive to fragmentation.

Size

The size of a SSD can be decreased further in the next years since NAND flash memories can become smaller and smaller. On the other hand, there are limitations in the decrease of the HDD size. The platter size is the problem.

Weight

The weight of SSDs is loghter since it has no motors, platters etc.

Failure rate

A mean time between failure rate of 2 million hours for SSDs and 1.5 million hours for HDDs.

 Overall, HDDs are more proper for massive data storage since HDDs are cheap drives. SSDs are more proper for fast data processing (fast boot time etc.).