hard disk drive

These devices are used for storing instructions and data permanently. They are also known as backing storage devices/auxiliary storage devices/secondary storage devices. They include DVDs, CDs, and hard disks. The storage devices that were used in early 1970 are still being used in the modern day because they were well-designed.

Why Do You Need to Use Secondary Storage Devices?

The following are the main reasons why people use these storage devices:

  • They can be used for storing a large number of instructions and data.
  • Ram (Primary memory) is temporary and volatile.

The following are the main types of auxiliary storage devices that you need to consider for your desktop or laptop computer.

Magnetic Tape

magnetic tape

These are the old storage devices that are made of magnetic materials. They are coated with plastic material. With these devices, information or data is stored in the form of spots (magnetic spots). The data is written and read on the tape using a tape drive. Magnetic disks are one of the sequential access devices, but they are relatively slow as compared to the optical or magnetic disks. These tapes are mainly used in reels that have different lengths including 1200, 600, 200 feet et.c.

DVD Rewritable (DVD-RW)

These disks can be used for writing data many times. The old data can be erased easily to create room or space for new one.

DVD-Recordable (DVD-R)

These are blank CDs that are used for storing data once. The data stored can be accessed easily, but it cannot be erased. They are mainly used for storing video movies. Data is stored on them using DVD writers.



These are the digital video disks which are used for storing information. They have small holes on their surfaces which are created using a laser beam. The tiny holes created are more than those found in the regular CDS. This means that they have a larger storage capacity than CDs. Most of them are pre-recorded, and they contain data such as software, movies, and videos.

CD recordable (CD-R)

They are used for storing data once just like the CD Roms. Initially, they are blank CDs that can be used once by the user. The data written on them can be read as many times as possible. This is the reason why they are referred to as Write Once Read Many. The devices used in storing data on them are known as CD Burners or CD Writers.