External storage refers to any type of storage device that can be connected to and accessed from a computer system. Unlike internal storage, which refers to components like hard drives and solid state drives that are built into a computer, external storage devices connect externally via USB, Thunderbolt, FireWire, or other ports. Some common examples of external storage devices include external hard drives, USB flash drives, SD cards, and optical disc drives.
What are the benefits of using external storage?
There are several key benefits that make external storage useful:
- Portability – External storage devices are designed to be portable so you can transport data between different computers. This makes them useful for transferring files or doing backups.
- Extra capacity – External storage provides additional storage space beyond what is available internally. This allows you to store more files and data.
- Convenience – External storage devices can be plugged in and accessed quickly without having to install them inside a computer. This makes them convenient for backups and file transfers.
- Security – Important files can be kept on external storage devices that are stored safely offline when not in use. This provides an extra layer of security against data loss.
- Expandability – Most computer systems have limited internal storage capacity. External storage allows this capacity to be expanded easily by just plugging in a new device.
What are some common examples of external storage devices?
Some of the most common types of external storage devices include:
External hard drives
External hard drives are portable storage devices that consist of a hard disk placed inside a durable external enclosure. They connect via USB, Firewire, Thunderbolt, or wirelessly. External hard drives come in a range of storage capacities typically from 500GB to 10TB. They can make great alternatives to internal hard drives for backup storage or accessing large media files.
USB flash drives
USB flash drives, also known as thumb drives, are small solid state storage devices with a USB interface. They come in capacities from 2GB to 256GB. Their compact size makes them easy to transport and use between different computers. USB drives are very useful for transferring smaller files and data.
SD cards
SD cards or secure digital cards are flash memory cards designed to provide storage for devices like digital cameras, mobile phones, and tablets. They come in sizes from 4GB to 1TB. SD cards can be transferred between devices via a USB SD card reader.
Optical discs
CDs, DVDs, and Blu-ray discs are examples of optical media that can be used for external storage. CDs store up to 700MB, DVDs store up to 4.7GB, and Blu-rays store up to 25GB. They make a great medium for long-term archival storage if properly maintained.
Solid state drives
External solid state drives use flash memory and are smaller and faster than external hard drives. They connect via USB and Thunderbolt interfaces. While more expensive per gigabyte than a hard disk drive, they are extremely durable since they lack moving parts.
What are the advantages of using external storage over internal storage?
There are several notable advantages that external storage can provide compared to internal storage:
- Flexibility – External storage devices can usually be used with any computer with the proper port and interface. Internal storage is fixed to a specific computer.
- Capacity – External storage allows you to expand storage capacity as needed by adding new devices. With internal storage you are limited to expansion slots and size constraints.
- Data protection – Important data stored on external devices can be kept physically secure when not connected to a system. This helps guard against data loss.
- Portability – Files stored on external devices can easily be transported and accessed from many different computer systems.
- Speed – New interfaces like USB 3.0 and Thunderbolt provide high speed connections for external storage devices that can match or exceed internal transfer speeds.
What are the limitations of external storage?
While very useful, external storage devices also have some disadvantages:
- They can be lost, stolen, or damaged more easily since they are physically detached from a system.
- Some external storage requires separate power sources or cables providing a physical tether.
- Interfaces like USB have slower maximum speeds than internal SATA or PCI connections.
- External solid state drives are currently considerably more expensive per gigabyte than hard drives.
- Larger external storage devices may require external power sources and be physically larger and heavier.
How is data stored on external storage devices?
External storage devices store digital data in various ways depending on the technology used:
Hard disk drives
Use magnetic recording on quickly rotating platters to store and read data. Data is stored in tiny magnetic regions across the surface of platters. Locations are accessed via an actuator arm with a read/write head.
Solid state drives
Store data in flash memory chips made up of silicon semiconducting transistors. Data is stored in tiny cells trapped with an electric charge that can be read or rewritten.
Optical discs
Store data in microscopic pits molded into multiple layers of plastic that are covered by a reflective metallic surface. A focused laser beam can then read or write data by detecting or altering these pits.
USB flash drives
Use flash memory chips to store data in rewritable grid of interconnected transistors. Apply voltage to trap electric charge allowing data to be rewritten multiple times.
SD cards
Utilize non-volatile flash memory in the form of electronically erasable programmable read only memory chips (EEPROM). Memory cells store charge allowing persistent storage.
| Storage Type | Interface | Capacity Range |
|---|---|---|
| External hard drive | USB, eSATA, FireWire, Thunderbolt | 500GB – 10TB |
| USB flash drive | USB | 2GB – 256GB |
| SD card | SD | 4GB – 1TB |
| Optical disc | SATA, PATA, USB | 700MB – 25GB |
| External SSD | USB, Thunderbolt | 120GB – 2TB |
What are the major applications of external storage devices?
External storage devices serve a variety of uses:
- Backups – External drives provide a great medium for backing up critical data from a main system.
- Archiving – The portability and expandability of external storage makes it useful for archiving large amounts of data.
- Transferring files – External drives and USB flash drives are extremely helpful for moving files between computers or locations.
- Expanding capacity – External storage can add large amounts of additional storage space for file storage.
- Media libraries – Large external drives work well for storing and accessing libraries of music, photos, and video.
- Data recovery – External drives can assist in recovering lost data from failed systems.
- OS boot drives – USB drives and SD cards can serve as boot drives to start up and run operating systems.
What are important factors when choosing external storage?
Here are some key considerations when selecting an external storage device:
- Interface speed – Faster external interfaces like USB 3.0, Thunderbolt 3, or USB-C allow for quicker data transfers.
- Drive speed – Solid state drives without moving parts offer faster read/write speeds than traditional hard drives.
- Capacity – Larger capacity drives can store more data but may require more power and be physically larger.
- Portability – Smaller, lighter devices are more portable while larger multi-TB drives typically stay stationary.
- Durability – Rugged, shockproof construction provides greater resilience especially for drives moved frequently.
- Security – Hardware encryption and password protection options help safeguard sensitive data.
- Compatibility – Check that drives support your OS and interface standards before purchasing.
- Budget – Less expensive drives typically offer less speed, capacity, and durability.
How can data be transferred to external storage devices?
Common ways to transfer data include:
- USB connection – Use a USB cable to connect the external drive to a computer and copy files like you would to an internal drive.
- Drag and drop – On supported OSes you can drag and drop selected files to the connected external drive icon.
- Copy/paste – Files can be copied from their source and pasted directly onto the external storage device.
- File transfer tools – Software like File Explorer on Windows or Finder on Mac provide file management tools.
- Disk images – Imaging tools can take snapshots of entire file systems and copy the disk image to external drives.
- Backup software – Backup utilities automate copying files from a system to external storage.
- File syncing – Apps can sync selected files and folders from a system to an external drive.
How can data be protected against loss on external devices?
Data stored on external devices can be protected in multiple ways:
- Keep backups on a separate external drive in case one fails or is lost/stolen.
- Use encryption technologies like BitLocker on Windows or FileVault on Mac OS to encrypt drive data.
- Store drives securely in locked locations when not in active use.
- Avoid excessive shocks, drops, vibration, heat, or magnetic fields that could damage drives.
- Enable password requirements on drives to prevent unauthorized access.
- Eject and safely disconnect drives using the computer OS before transporting them.
- Handle drives carefully by their edges and avoid touching connectors to prevent damage.
- Scan external drives periodically for malware or errors using antivirus tools.
- Purchase drives from reputable vendors and registered resellers when possible.
Conclusion
External storage devices provide versatile options for expanding storage capacity, protecting data, and enabling file accessibility and transportability. Choosing drives with higher speeds, security features, and durable designs can maximize performance and data protection for your use case. Following best practices around encryption, physical handling, backups, and drive maintenance can help reduce risks. With large affordable capacities and fast new interface standards, external storage enables data storage flexibility and conveniences that make them a staple of modern computing.