A few years earlier we all used mechanical hard drives to store our data in computers. The first HDD was invented in 1956 by IBM replacing the huge and costly magnetic tapes and punch cards. In 1991 SunDisk company introduced the first commercial SSD (Solid-state drive) to the market. Both storage devices have cons and pros. Solid-state drives are expensive, fast, and durable while the hard disk drives are inexpensive, comparatively slow, and less durable. Most computer users use a combination of HDD and SSD on their computers to maintain a super fast speed at a low cost. HDD uses magnetic materials to store digital data. But, SSD uses electric pulses to store data.
In this article you can learn everything about HDD and SSD and get a proper knowledge on which one to choose or which combination to use.
What is an HDD
A hard disk drive is an electro-mechanical data storage device. HDD store data on rapidly rotating platters with the magnetic material coat. Digital data is actually stored as different magnetic levels which can be read by the read-write laser header of the hard disk drive.
Modern Hard disk specifications
Consumer hard disks generally operate in the 5400 RPM to 10,000 RPM speed range. Fastest hard disks available in the market have an RPM of 15,000. But, these high-speed hard disks are generally used in applications which require a very high data speed such as server machines and online clouds. After the evolutionary solid-state drives were introduced these high-speed hard disk drives are no longer required to achieve those high data speeds.
This RPM or round per minute indicates how many rounds your hard disk’s plotter can rotate in one minute. Faster the RPM faster your data speed is.
7200 RPM is the most common plotter speed used in desktop computers. These HDD’s have a read-write speed of 80-160 Megabytes per second. Laptop hard disks are smaller in size comparing to a desktop HDD. (Not the capacity) So, the typical RPM of a laptop hard disk is 5,400 RPM. According to the famous HDD manufacturer Seagate, the 7,200 RPM HDD is 33% faster than a 5,400 RPM HDD.
Hard drives or HDD are cheap and the cost per storage unit is much cheaper than SSDs.
A few years earlier we just had HDDs with gigabyte capacities. But, today most HDD’s have a capacity above 1 terabyte. (which is 1000 Gigabytes) In 2019 the HDD with the highest capacity of 15 terabytes (15000 GB) was introduced to the market.
Did you know? According to scientists the capacity of a human brain is somewhat around 10- 100 terabytes. A decade ago no one imagined that we could own a computer with a storage capacity equal to a human brain. We are living in the future.