Differences between HDD’s and SSD’s: A layman’s guide on hard drives
Gone are the days when you only had to decide the capacity of your hard drive for storage, while purchasing a new laptop. With the recent advancement in technology you now have a choice between a SSD or a HDD to handle your storage requirements. So which one should you go for?
What are HDD’s?
A hard disk drive (HDD) is a data storage device used for storing and retrieving digital information using rapidly rotating disks (platters) coated with magnetic material. A read/write head floats above the spinning platter reading and writing data using magnetism and the magnetic material. The faster the platter spins, the faster an HDD can perform. Typical laptop drives today spin at either 5400 RPM (Revolutions per Minute) or 7200RPM though some server-based platters spin at up to 15,000 RPM. HDD’s have been around for 60 years and provide the cheapest way to store data in a device.
What are SDD’s?
A solid state drive (SSD) is functionally similar to a HDD, but instead of a magnetic coating on top of platters, the data is stored on interconnected flash memory chips that retain the data even when there’s no power present. In simple words, consider the SSD as an advanced and glorified version of a Memory stick or a thumb drive, more reliable and efficient. The main difference between a SSD and the HDD is that SSD does not have a mechanical arm to read and write data, it instead relies on an embedded processor called a controller to perform a bunch of operations related to reading and writing data. The controller makes decisions related to how to store, retrieve, cache and clean up data can determine the overall speed of the drive.
Let us have a look at the key factors that separate these two drives:
Because HDD’s rely on spinning platters and heads, there is a limit to how small they can be manufactured. SSDs on the other hand do not have any moving parts and hence have so such limitations, they are a lot smaller in size and lightweight as compared to the HDD’s
This is where the SDD’s true abilities come into the picture. A PC or Mac with an SSD boots faster launches apps faster, and has higher overall performance as compared to a HDD based system which takes time to boot and is also slower than the SSD during normal operation. An SSD also provides faster transfer speeds with respect to external devices as compared to an HDD
SSD’s are generally expensive in terms of cost per capacity. A 1 TB internal HDD costs around 4000₹. While a 1 TB SSD costs around 30000₹, the price difference is even more as the capacity increases. Such drastic differences in price are one of the most influential factors in the choice between an SDD and an HDD.
HDDs offer maximum storage capacities ranging from 1TB to 4 TB, while SSD’s max out at around 1 TB. Even the 1 TB SSD’s are very expensive and hard to find, with the norm for SSDs ranging from 128 GB to 500 GB. If you are dependent and store most of your data on the cloud, SSD’s might work out for you. But if you like to store all your data on your system, there is nothing better than an HDD to do your bidding.
SSDs are viewed as more durable simply because of their solid state design. Without moving parts, they can withstand higher extremes of shock, drop and temperature. This does not necessarily mean that HDD’s are not reliable but like any device with moving parts, you can never be too sure.
Both SSD’s and HDDs wear out over time. But a HDD drawback is that the data contained in it can be erased when it comes in contact with magnets while magnets have no effect on the SDD’s. Although this is something very minor and chances of this happening are few and far in between, it can still be a deciding factor.
Even the quietest HDD will emit a bit of noise when it is in use from the drive spinning or the read arm moving back and forth. The faster the device the more noise it makes. SSDs make virtually no noise at all, since they’re non-mechanical.
Because of their rotary recording surfaces, HDD surfaces work best with larger files that are laid down in contiguous blocks. That way, the drive head can start and end its read in one continuous motion. When hard drives start to fill up, large files can become scattered around the disk platter, which is otherwise known as fragmentation. While read/write algorithms have improved where the effect in minimized, the fact of the matter is that HDDs can become fragmented, while SSDs don’t care where the data is stored on its chips, since there’s no physical read head. SSDs are inherently faster.
The comparison here is just to lay out the pros and cons for both options, Choosing the perfect drive depends upon your requirements, if price, capacity and availability are your main motivations then you are better off with the tried and tested HDD’s. If speed, reliability and form factor are you main requirements and price is not a factor then an SSD is the perfect drive for you.
If you still are undecided currently there are many SSHD’s (Solid State Hybrid Drives) available in the market, that offer the best of both the drives adding the speed of SSDs to the cost-effective storage capacity of traditional HDDs, Which make for a better option.