External hard drive: what it is and what it is for

If you've reached this entry, you probably don't know what an external hard drive is. Or you may know them, even use them regularly, but want to know more about them. Whatever your case, in this post we will explain what an external hard drive is and what it is for.

The standardization of cloud storage and on-demand playback services have decreased the amount of data we need to store on our computers; However, we still have a large number of files and documents that we do not want to get rid of, resorting to traditional storage systems for it.

Index of contents

What exactly is an external hard drive

When we talk about an external hard drive, we are referring to a hard drive (or HDD) connected to our computer from the outside by external means, usually via USB. These storage devices are used as a traditional internal disk, in which to store information from our equipment. This definition also includes solid state drives (or SSDs), but the term "external disk" is commonly used without distinction between the two.

SATa-USB adapter for a 2.5 "drive

From the above paragraph, we might think that there are no differences between a traditional flash drive and an external hard drive, but the differential factor between the two is their format: external hard drives are usually internal storage devices that have been embedded in a case. This is easily verifiable by opening one of these devices, or checking how casings are sold (without a drive inside) to create our own external drives.

A transparent external hard drive enclosure. Inside is a common HDD.

The aforementioned housings serve as adapters and are what give these devices their connection interface. As we have already written, the most common is USB, but we can also find FireWire, Thundervolt, eSATA, and even wireless (WiFi). Most of these units do not require more than their connection interface for their power supply, but in some cases they require a power cable.

What are external hard drives used for?

Given their nature, external drives are eminently portable and allow you to easily enter, transport, or copy large amounts of documents and files from one computer to another. In addition, since they do not need to be inside the equipment to function, they are the preferred option to expand the storage of equipment with difficult access; Some examples of this would be laptops, or mobile devices, which find more utility in external disks compared to lighter options, such as USB flash drives .

The main reason for the last affirmation of the previous paragraph, is that the internal disks that give life to these devices have greater capacity and durability than a traditional pendrive , so they can be used without problems as a direct expansion of system storage, even using them. as a backup copy of it.

External disks do not behave like internal ones

At this point, some readers might wonder why, given their convenience, we do not use this format to the detriment of internal hard drives in all of our devices.

The main reason is the way in which these devices communicate with the rest of our teams. The internal hard drives are connected to our computer through SATA or NVMe (PCIe) interfaces, which have a direct connection to the motherboard and the components connected to them. Both interfaces are faster and work better under load than those found on external drives, where SATA can reach 600MB / s and constant 1GB / s PCIe, compared to USB 3.0 and its maximum 640MB / s. In addition, internal hard drives are often used to load system files and on external drives, the content is usually around multimedia.

Despite this, the usefulness of this type of external units is undoubted and they are one of the most popular accessories in consumer electronics. That is the main reason why we have decided to dedicate an article in which to specify what an external hard drive is and what it is for.

WE RECOMMEND YOU How to connect two computers via WiFi network

If you want to know more about these devices, or would like to know our purchase recommendations for the best external hard drives on the market. What external hard drive do you usually use?