Is a flash drive an input or output device?

Understanding whether a flash drive is an input or output device will help figure out how all the other parts of a computer fit together too. Flash drives or USB flash drives are incredibly common in today’s technologically driven world and form a crucial part of people’s hardware setup. 

A flash drive is not an input or output device, it is a storage device. A flash drive can store all of your digital content including music, videos, documents, and apps. They are smaller, faster, and a lot more reliable than floppy disks or CDs, which were the data storage devices of choice before flash drives were invented. Their usefulness explains why the market for flash drives has exploded and nearly trebled in just 7 years, 

Memory pens allow for up to 100,000 write and erase cycles, so it’s easy to understand why people can confuse them with an input or output device. 

Let’s take a closer look at how they interact with the rest of your computer and understand why flash drives are storage devices. 

Is a flash drive an input or output device?

The flow of data with a flash drive

A flash drive is a storage device, not an input or output device. It uses flash memory similar to that used by RAM to store your files and applications but retains all data when unplugged. A flash drive is sent data to store by your CPU, which then retrieves it when needed at a later point. 

Flash pens have become incredibly popular because they allow people to create a backup of their data, and transport it with ease. The maximum storage capacity for flash drives is around 2TB and these can typically last anywhere from 10 to 100 years before failing. Your hard drive, which is also a storage drive, has a lot of moving parts and is a lot larger than most memory pens. Flash pens are a lot more reliable because they have no moving parts and the data is stored in a chip rather than on a physical disk. 

The control unit in your computer’s central processing unit is responsible for sending data back and forth to various storage devices. We can use the diagram above to walk through a typical flow that would involve a flash pen.

Using an input device like a scanner, you can upload documents to your computer. However, you may not want to take up space on your hard drive with random documents or images. Or you could be using a public computer where you don’t want sensitive information to be stored. The scanner would send the data to the CPU which would then work with your hard drive to store a copy of the document.

During this process, your CPU would continually be sending information to output devices like the monitor to keep you updated with the progress. To move the scanned data to a flash drive you would locate the file on your hard drive and then transfer it to the USB memory pen. The CPU would then send various instructions via traces on the motherboard to the relevant devices. Finally, the file would then be sent to the flash drive.

In the example above, the various input and output devices are either sending or receiving data from the central processing unit as their primary purpose. However, the flash drive’s primary purpose is to store the data it has received.  That is a major difference and why a flash drive is not an input or an output device. 

Why is a flash drive a storage device?

A flash drive is a storage device because its primary function is to store data that it receives from the central processing unit. Then it is used to retrieve that data at a later point when the user or the system needs it. However, unlike traditional storage devices, a flash pen can be easily removed and transported.

A flash drive does send and receive data from the CPU. It is also readable and writable which is why some people confuse it for an input or output device. However, it’s important to remember that in the context of a computer we have four main types of devices:

  • Input devices
  • Output devices
  • Storage devices
  • Processing devices

The components of a computer are separated like this so understanding the flow of data is simpler. Various components in a computer can input and output data but if this is not their primary function they should not be referred to as such. The CPU inputs and outputs data but it is primarily the brains of your computer and a processing device. Your speakers do send small pieces of data back to the CPU but its main job is to output sound, hence why it’s referred to as an output device. 

It is crucial to separate devices by the tasks they perform. A flash disk stores all the data you need it to. Therefore we must refer to it as a storage device because this is the main job it performs in a computer.

​​Is a USB flash drive an input or output device?

A USB flash drive is not an input or output device, it is a storage device that holds all the files or data that you need it to. They generally hold anywhere between 8GB and 2TB of data which is held in flash memory on a chip inside the USB stick. 

Other names for a USB flash drive include a pen drive, thumb drive, or sometimes just a USB. Regardless of how it is referred to, a USB flash drive always operates as a storage device and not an input or output device.

Most devices have some sort of two-way communication with the CPU even in some small doses. Therefore, it’s important to define them by the functions they perform. If a piece of hardwares main purpose is to send data to the processor, it is an input device. If the device primarily receives data from the process and outputs it, then it’s an output device. A USB flash drive’s main purpose is to store data it receives from the processor. It then keeps hold of it and sends it back when requested.


A flash drive is a storage device that provides additional storage for your computer or mobile device. They are an incredibly reliable form of storage due to the lack of moving parts and can be easily transported because of their small size. 

A USB flash driveutilizess flash memory which is similar to that found in your computer’s RAM. However, unlike with RAM, the data persists even when the device is unplugged.

A flash drive does send and receive data, but it does not make it an input or an output device. It is first and foremost a storage device that keeps data and then returns the data when requested by the user.