Different Types of Hard Drives

Before we get to the various different types of hard drives, let's go through a brief session on what hard drives are. Previously known as hard disk drives, hard drives are storage devices for backing up digital data. The best feature of these devices are that they are non-volatile as they are capable of retaining stored data upon them even when unplugged from the power source, unlike RAM which loses all information as soon as the computer is shut down! Data if encoded magnetically upon such drives using read/write heads. These heads hover above the disk platters as if they are riding upon an air valve. Broadly, there are two different types of hard drives - internal and external. What is an internal hard drive? An internal hard drive is the disk drive that is inbuilt within the computer/laptop and which comes as a part of the factory assembly of the entire system. What is an external hard drive? Let's find out.

External Hard Disk Drives

An external hard drive is that which can be externally connected to the computer/laptop using USB ports. Portable hard drives and pen drives are such examples of external hard drives. EIDE, SATA and SCSI are all examples of external hard drives and these are being discussed subsequently. These types of external drives are usually enclosed within portable disk covers and the connecting interface may be any among USB, eSATA, eSATAp, etc.

Now, let's proceed towards discussing the various different hard drive types based upon narrower technological details and features.

What are the Different Types of Hard Drives?

Based upon technical details and functionalities, there are four major types of hard drives that are commercially available as of this date. These four hard drive types are being discussed below under separate headings.

Enhanced Integrated Drive Electronics: More commonly known as PATA (Parallel Advanced Technology Attachments), EIDEs are not very popular these days as advanced technologies in the form of SATA have captured a lion's share of the hard drive consumer market. The labels on these drives correspond to the interface variant which is involved to connect the CPU board and the drive together. The latest and faster EIDE variants use cables of 80 wires, although the older versions worked mostly on 40 wire cables. The connector used in these drives are usually 40-pin variants. Formatting a hard drive of this category may take a longer time due to slower speed.

Serial Advanced Technology Attachments: Commonly known by its abbreviated name SATA, these hard drives are identified apart from their precedent, EIDE or PATA due to a different variant of connector incorporated in the former. Also, EIDEs are bulkier than their successors, SATA and the former's data interface is slower than the latter's. Also, SATAs score on the power consumption front as they consume lesser power than EIDEs.

Solid State Drives: Abbreviated as SSD, these hard drives are composed of stationary parts. There are no moving paraphernalia in these drives, as opposed to other hard drive variants which usually include magnetic disks that rotate as they back up data. SSDs are equipped with semiconductors which perform the task of rotating magnetic disks to pile up saved data. The absence of moving parts within the drive means it is less susceptible to break downs and their processing speed is faster than other drives that employ the conventional storage methods! This is what ranks SSDs as the best external hard drives as far as speed and durability is concerned!

Small Computer System Interface: Known by its short form SCSI, these drives function in similar ways as EIDEs insomuch as they employ rotating magnetic disks to write and save data upon them. The major difference between SCSI vs EIDEs and SATAs is the fact that SCSI drives spin faster than either of the aforementioned hard drive types. Faster spin rate means faster data processing and storage. However, the flip side of fast rotation rate is that the faster the disk rotates, the faster the drive is likely to break down! This makes attempts to repair bad sectors on hard drive difficult for these types.

That was a bird's-eye glance over different varieties of hard drives. It helps to know what type of hard drive your system is using as some basic knowledge about hard drives (such as reformatting, booting/rebooting, etc.) would help you troubleshoot that corrupted hard drive yourself! However, if you are not a computer hardware engineer, soliciting professional troubleshooting is a better idea! Why compromise your entire system for the sake of a malfunctioning storage device? Happy computing!