What is Secondary Memory in English

Secondary Memory

The name of Secondary Memory itself shows that it is separate from the primary memory of the computer i.e. it is not an internal part, the secondary memory is added separately to the computer. It is also called Secondary Memory of the computer. so further we all will know what is the secondary memory of the computer.

What is Secondary Memory in English

Secondary memory is added separately and when it is used for storage, it is also called secondary storage device, its speed is less than primary memory but its storage capacity is primary memory. ) Is high and can be upgraded (reduced or increased) when needed.

Secondary memory divided into 4 types

1. Magnetic Tape
2. Magnetic Disk 
3. Optical Disk
4. USB Flash Drive

Magnetic Tape

It looked like a cassette of an old-fashioned tape recorder, with a layer of magnetic material mounted on a plastic ribbon, on which the head was used to store the data, just like a tape recorder, this data Of how many times could be written and erased and it was very cheap.

Magnetic Disk 

Magnetic disk divided into two types

1. Floppy Disk
2. Hard Disk Drive

Floppy Disk

Floppy Disk is a round disk of very thin plastic which was closed in a plastic cover, this disk was covered with a layer of magnetic material, floppy disk depending on the size and storage. There are two types.

Mini Floppy - Mini Floppy has a diameter of 3½ inches and has a storage capacity of 1.44 MB. It requires a 3½ inch floppy disk reader to be read into a computer. It rotates at a rate of around 360 RPM i.e Revolutions Per Minute.

Micro Floppy - Micro Floppy has a diameter of 5½ inches and a storage capacity of 2.88 MB, also requires a 5½-inch floppy disk reader.

Note - In computers "A" and "B" drives were used for floppy disks and even today "A" and "B" drives are reserved only for floppy disks, although it has been completely discontinued.

Hard Disk Drive

Let us tell you that the world's first manufacturer of Hard Disk Drive is IBM, which was made in 1980, it is an aluminum metal disk on which the material is coated, this disk is located on a spindle. Rotates rapidly and its speed is measured in RPM i.e. Revolutions Per Minute ie round / rotation per minute,

Today it is available in the market with a Hard Disk Drive with 5200 RPM and 7200 RPM, Hard disk drives have track and store data in the sector. One sector stores 512 bytes of data, an 80s hard disk drive whose first partition was named "C" drive and today when you install Windows, it is first installed in the "C" drive.

If you talk about storage, Hard Disk Drive is used as the main secondary memory. Currently, hard disks ranging from 1 terabyte to 100 terabytes are available.

Optical Disk

The optical disk consists of a round disk of poly carbonate, which is coated with a chemical substance. The optical disk (optical disk) data is digitally protected, the data is read and written to the optical disk. Low-capacity laser light is used to, Optical discs are divided into three types.

1. CD
2. DVD
3. Blu Ray

CD

The full name of the CD is Compact Disk, its capacity is less than hard disk and more than Floppy Disk, it can store some 700MB of data, it can keep data safe for about 30 years, But when there is a scratch on its surface, it is difficult to read and write the data.

DVD

The full form of DVD is Digital Video Disk or Digital Versatile Disc.DVDs have a much higher storage capacity than CDs, but they both look the same, but DVDs have a storage capacity of about 4.7 GB to 17 GB, But here is the problem with the scratch.

Blu Ray

Blu Ray is similar to watching CDs and DVDs, but the laser light used to read and write it is a blue-colored violet ray, so it is called Blu Ray. Go, because of this light, up to 50 GB of data can be stored on a Bluetooth disk.

USB Flash Drive

It is currently the most popular and portable secondary memory device which is connected to the computer via USB port which we also call as pen drive, it is used to save data other than video, audio.

Read Also

Register Memory
Cache Memory
Primary Memory