Can you use USB as an external drive?

Yes, USB drives can be used as external drives to store and transfer files. USB drives, also known as flash drives or thumb drives, are small, portable storage devices that plug into a computer’s USB port. They provide a convenient way to add extra storage space without having to install an internal drive.

What is a USB drive?

A USB drive is a type of portable storage device that uses flash memory and connects to a computer via a USB port. Flash memory is a type of electronic memory that can be erased and reprogrammed. It retains data even when power is turned off.

USB drives are small, lightweight and easily portable. They come in capacities ranging from 1 gigabyte (GB) up to 256 GB or more. Higher capacity USB drives are ideal for storing large files or serving as expanded storage for a computer system.

How does a USB drive work as external storage?

When you plug a USB drive into a computer’s USB port, it is assigned a drive letter and appears as an external drive in the file system. The USB connection provides power to run the flash memory chip and allows data to be transferred back and forth.

Standard full-sized USB drives use a Type-A USB connector that plugs into the rectangular USB ports on computers. Smaller, ultra-compact USB drives may use a Type-C connector. Cables and adapters are available to connect various types of USB drives to smartphones, tablets and other devices with Micro-USB or USB-C ports.

USB drives interface with the computer using the same system calls and protocols as an internal hard disk drive. This means the operating system treats them as another storage device, making them plug-and-play external drives that can be used like any other drive for file management tasks.

Benefits of using a USB drive as an external drive

There are several advantages to using a USB drive for external storage instead of other methods:

  • Small size and portable – USB drives are compact and lightweight enough to carry in a pocket.
  • Reusable – Files can be erased and the drive reused over and over.
  • Runs on USB power – USB drives get power from the USB port so no external power adapter is required.
  • Plugs into any USB port – USB drives can interface with PCs, Macs, and even smartphones and tablets with USB ports.
  • Strong storage capacity – Higher capacity USB drives can hold a substantial amount of data.
  • Cost effective – The price per gigabyte of storage is low compared to many other data storage products.
  • No installation required – USB drives work as plug-and-play storage with no drivers or installation needed.

For quickly transferring files between computers, expanding storage space, making backups and many other storage needs, USB drives offer an efficient and practical solution.

Using a USB drive for file storage and transfers

To use a USB drive for file storage and transfers:

  1. Insert the USB drive into an available USB port on your computer.
  2. The drive will appear as an external disk drive and be assigned a drive letter.
  3. Use file manager to access the drive and drag-and-drop or copy/paste to transfer files back and forth.
  4. Open files directly from the USB drive or copy them over first.
  5. Edit files on the USB drive with applications like Microsoft Office.
  6. The drive can also be ejected and files accessed from another computer.
  7. When finished, use the “Safely Remove Hardware” option before unplugging the USB drive to avoid data loss.

Once the USB drive is inserted, it functions just like any other disk drive. Files can be managed, edited, opened, saved and transferred to and from the USB drive as needed. Using common file operations like copy, paste, drag-and-drop, open and save, the USB drive is simple to integrate into any workflow.

Advantages over other external storage options

Compared with other external storage options like external hard drives and memory cards, USB drives have several advantages:


USB drives are smaller and lighter than external hard drives, allowing extreme portability. They can fit into a pocket or bag and be carried anywhere.


Higher capacity USB 3.0 drives now offer terabytes of storage space on small thumb drive devices. This is sufficient to store even very large files and disk images.


USB 3.0 drives have transfer rates up to 5 Gbps, making them faster than external hard drives using older USB standards.


USB drives plug directly into any USB port without cables or power connections. They are as simple to use as plugging in a keyboard or mouse.


USB drives work across PC, Mac, Linux, Chromebook and mobile devices. External hard drives may have OS or device compatibility limitations.


With no moving parts, USB flash memory storage is less prone to failure or damage from physical shock compared to hard drives.

For general external storage needs, USB drives provide an unmatched combination of performance, capacity, size, and simplicity.

Using USB drives for backup

In addition to file transfers and external file storage, USB drives work well for backing up important files.

To use a USB drive for backups:

  1. Insert the backup USB drive into your computer’s USB port.
  2. Use the file manager to create a dedicated folder on the drive for backups.
  3. Copy important files and folders to the backup folder on the USB drive.
  4. Eject and safely remove the USB drive when finished.
  5. Store the USB drive in a safe place when not plugged in.
  6. Connect the USB drive regularly to run backups per a schedule or as needed.

Advantages of using a USB drive for backups:

  • External media allows backup files to be stored safely off-site from the original data location.
  • Flash media helps protect backups from risks like power surges, operating system crashes, ransomware, or other threats to the live computer system.
  • Backups can be automated using the Windows Backup tool or 3rd party backup software.
  • Multiple backups can be stored on one high-capacity USB drive.

USB drives provide an excellent medium for file backups to protect your data from loss or disasters.

Booting an operating system from a USB drive

In addition to storage, USB drives can also be used to boot desktop computer systems or run operating systems portably.

Most computers support booting from a USB drive, allowing it to act as the primary boot device instead of the main internal hard drive. This lets you boot into alternative operating systems for troubleshooting, rescue and recovery, installation, or other maintenance tasks.

To create a bootable USB drive:

  1. Insert your USB drive into a computer with the operating system ISO file you want to make bootable (e.g. Linux distro disc image).
  2. Use bootable USB creator software to extract the ISO to the drive and make it bootable.
  3. Reboot your computer, enter BIOS settings, and select your USB drive as the temporary first boot device.
  4. Boot from the USB drive to load the desired operating system.

Booting from USB is useful for:

  • Installing or reinstalling operating systems
  • Running diagnostic tools to troubleshoot hardware or software problems
  • Booting into alternative operating systems like Linux for system rescue and recovery
  • Loading a temporary, portable operating system without installation

With bootable USB drives, you can access many operating systems on demand from the convenience of your pocket.

Potential drawbacks of USB drives

While very useful, USB drives do come with some downsides to consider:

  • Small size makes them easy to lose – Their compact form factor also means they’re easy to misplace and lose.
  • Not as durable as hard drives – Without spinning platters and protective casings, USB drives are more fragile if abused or damaged.
  • Prone to failure – USB drives still have a failure rate that increases with heavy long-term use.
  • Slower than internal drives – USB has speed limitations, so USB drives may be slower than internal SSDs or multi-disk RAID arrays.
  • Not well suited for primary storage – The drawbacks above make USB drives unsuitable as primary long-term storage devices in most cases.

While the simplicity and portability of USB drives are big advantages, they come with tradeoffs. For primary or sole storage of important data, internal hard drives or external hard drives/NAS systems with redundancy may be preferable.

Choosing a USB drive

With a wide range of USB drive products available, here are key factors to consider when choosing one:

Storage capacity

Capacity ranges from 1 GB to 256 GB or more. Choose sufficient capacity for your intended use – either a typical file transfer stick, or a higher capacity backup or bootable drive.

Physical size

Standard USB drives are approximate 1.5 x .75 inches. Low profile and mini drives are available for extra portability.

Transfer speed rating

Faster USB 3.0/3.1 drives offer 5-10 Gbps transfer speeds. USB 2.0 drives are slower at around 30 Mbps.

Build quality

Metal encased USB drives tend to be more durable than plastic versions.

Security features

Encrypted USB drives add an extra layer of data security and can prevent unauthorized access.

Once you settle on the right storage capacity, form factor, speed and features, you’ll be ready experience the convenience of running your own portable external drive via USB.


USB drives offer an extremely handy, fast and user-friendly external storage option. Their plug-and-play simplicity, vast capacity, tiny size, and universal compatibility make them one of the most versatile data transfer and expanded storage mediums available.

USB drives excel at file transfers, backups, storage expansion, booting operating systems and numerous other uses. While they have some vulnerabilities, their strengths and flexibility make them a storage solution no PC user should be without. USB ports are everywhere, so compatible external storage is always at your fingertips.