Flash Storage

What is Flash and Why is it Increasingly Becoming More Popular?

12/04/16 | in: Storage | by: Jack Blogg


HDD: Hard Disk Drive, traditional spinning disk storage.

SSD: Solid State Disk, storage that doesn’t require moving parts.

What is Flash?

The Basics:

Flash storage is any type of data or storage system that uses flash memory. Flash memory is a kind of memory that retains data in the absence of a power supply, basically unlike other forms of storage flash can retain information when the power is switched off.

Why Flash?

There are 5 main factors which should be considered when making a decision to upgrade to a flash storage system:


This is where flash comes into play, HDD’s take a lot longer to access data as they require time for the disks to spin, whereas with Flash SSD’s they can be accessed almost instantaneously – latency times with flash are almost non-existent.


As we know HDD’s are made up of spinning disks, this makes a Hard Drive much more vulnerable to damage from common issues such as overheating.


It is hard to judge capacity overall as everyone scales differently, however, if we look at capacity per disk, comparing HDD and SSD, HDD has the greater capacity.


Traditional hardware is generally cheaper than flash, this is mainly due to flash being a newer form of storage but as time has gone on since the introduction of flash it has gone down in price, almost to an equal level these days. It is also important to consider running costs, a HDD is made up of spinning disks so requires a lot more power compared to SSD.


For a long time the actual density of storage on solid-state storage devices per surface area has been much less than that of HDDs, however flash has now exceeded HDDs, meaning flash takes up less physical space. This is mainly due to the increase in capacity of flash/ SSD chips. The different chip versions can be categorised as follows:

Abbreviated Name Name Density Performance Price Endurance
SLC Single Level Cell 1 bit per cell High £££ High
eMLC Enterprise Multi Level Cell 2 bits per cell Good ££ Average
MLC Multi-Level Cell 2 or more bits per cell Average ££ Average
TLC Three level Cell 3 bits per cell Low £ Low

Overall both forms of storage have their benefits, however flash is fast becoming the most popular form of storage due to its speed and as this technology has developed manufacturers are increasing the speeds at which SSD’s operate.

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