Storage Devices

Overview

       Since the advent of internet, data science has eminently gained importance and still continues to be a challenging field. It is astonishing! how much you could know and deduce about a person just by collecting his/her data. Amidst such a situation, knowing about storage devices is salient and it is paramount to be savvy when you choose a storage device for your computer. 

In this post, I'll be comparing the two pivotal storage devices that are in use today: Hard Disk Drive (HDD) and Solid State Drives (SSD).

What are Hard Disk Drives?

        HDDs are one among the oldest storage devices still at use in the contemporary world. They were first introduced in IBM devices in the year 1956 (Yeah that's way older than many of us!). A HDD at present can store up to 4TB-10TB of data on a desktop computer!

 

 

So how does a HDD store data??

First let us begin by identifying the main parts of a HDD:

• Platters: for storing data.
• Spindle: to keep the platter in position and rotate it.
• The Read/Write arm: as the name suggests, for reading and writing data.
• Actuator: Typical motor to control the actions of read/write arm
• Other components such as power suppliers and connectors

-- A HDD stores data magnetically on to the platter. The platter keeps rotating about the spindle upon which the read/write arm hovers writing data on to it or retrieving data from it. The speed of a HDD is based upon how fast the platter can spin. Typical Laptop drives spin at 5400RPM(Rotations per Minute) to 7200RPM. Although some higher end HDDs have rates up to 14000RPM!

What are Solid State Drives??

      Almost everyone uses HDDs, but we might have come across SSDs when we were shopping for a computer and wondered why does the same computer with same configuration, except with an SSD costs a fortune. 

      
   A SSD is a storage device with literally no moving parts in it. It is made up entirely of microchips and controllers and all the data is stored and retrieved from it. You can re-imagine it to be an amplified pen drive. A SSD uses NAND based flash memory which is non-volatile and present day SSDs can store data up to 16TB! Coming to the aspect of speed; the speed of a SSD depends on the quality of controllers in it. a high end SSD with SATA interface is capable of read/write speed of up to 712MBps.

Why are SSDs faster than HDDs?

      The data in HDDs are stored magnetically, they need to be converted to electric signals to be readable which takes up extra effort and thus makes it a slower device; also they use mechanically moving parts to retrieve data which makes it slower. Meanwhile, the SSDs store data in microchips in the form of electric signals resembling 1's and 0's. Thus the information can be swiftly retrieved compared to a HDD. In addition to that, since the SSDs build is completely electronic and works faster than HDDs they cost twice that of HDDs for even less storage capacity.

HDD v/s SSD! 

• Data durability: SSDs can store data for a very long period of time given the condition that, it needs to be connected to power supply often. On the contrary, a HDD can also store data for longer periods (even without power supply) but, it would wear out because of the mechanical parts employed in it there by reducing its durability.
• Cost: SSDs are very expensive compared to a HDD while giving you less storage capacity at more than twice the cost of HDDs.
• Start up time: SSDs are almost instantaneous, taking just a few milli seconds; on the other hand, HDDs take up considerably long time on first boot up.
• Noise: SSDs have no moving parts and hence make zero noise; while, the HDDs are made up of mechanical moving parts; they tend to make characteristic sounds like whirring and clicking.
• Affect of magnetism: SSDs are not stirred by magnetism and the data remains intact. On the other hand, data in HDDs are erased in the vicinity of magnets.
• Encryption: Both SSDs and HDDs offer a Full Disk Encryption. 
• Heating: SSDs produce little heat since it draws less power and has no moving parts; on the other hand HDDs can heat up to significant levels due to their mechanical build.

Which type of storage suits you?

You need a HDD if:

• You require a lot of storage space (Eg: 4TB-10TB)
• Your budget is less
• Not worried too much about intricate details of speed performance.

You need a SSD if:

• You are a professional and has to store data securely for long term.
• You need a faster performance (faster boot up and application run)
• You are willing to work your way around limited storage.