A hard disk drive (HDD) is a random access non-volatile digital data storing device. It has a rigid platter which rotates on a spindle which is motor driven. All this is enclosed in a protective covering. There is provision for magnetically reading and writing the data with the help of a air film that floats above the platter. It was for the first time introduced by IBM in the year 1956 and has been used as a secondary storage device.

A solid state drive very commonly known as a SSD is a storage device. It uses solid state memory to store the data and this data is easily accessible. SSD has no moving parts and contains microchips, which store the required data in non-volatile memory chips. SSDs are commonly used these days and are less susceptible to shock and have less access time and also latency. These have almost replaced the hard disk drives which had many drawbacks. In the year 2010 the SSDs used NAND flash memory. These had the capacity to store data in their memory even without the power. The SSDs with a volatile RAM were also available for times when the requirement for fast access of data was needed. They also can store data when there is no power and hence there is no need for an external battery.

The prices of the hard disk drives are falling day by day while the solid state drives are consistent in the cost part. The price fall of the HDD is such that now it’s even less than the SSD. The fall in the price of the HDD may be due to the growing laptop market in the present time. The laptop market uses the SSD specifically the ones which are flash memory based. This is because this flash memory based SSDs are faster than the HDDs and in some cases as seen in recent times they can prove to be much faster than the HDDs. Purchasing an SSD can be a luxury when compared to a HDD because SSD costs 10 to 20 times more than a HDD of the same magnitude. If we take the example of Apple MacBook, we see that upgrading the drive from a 320GB HDD to a 256GB SSD increases the cost of the system by $650, when we see that the capacity of the HDD is much greater than the SSD. The retail SSD costs a bit less from top tier suppliers still it is nowhere close to the HDD pricing of the same or even higher capacity.

SSDs are a prominent device when laptops are concerned but they have not gained the same amount of prominence in personal computers because of the high price value. HDD has a higher capacity with a lower price and since the question of portability does not arise in case of personal computers, people prefer sticking to the much lower in cost HDDs.