Hard Disk Drive

HARD DISK DRIVE

SLIDE CONTENTS

What is a hard disk and how does it work?

How have hard disks changed? - Appearance - Power requirements Who invented it? Conclusion References

WHAT IS A HARD DISK AND HOW DOES IT WORK?

A hard disk drive is non volatile storage device ( Retains information when not powered) that stores digital data on a magnetic surface. The device usually consists of several motorised magnetic disks and a motorised drive head to read and write information. The device is then cased in an aluminium casing to protect the delicate parts.

Power requirements of a hard disk are generally quite low however significant effort is still put into reducing this requirement to make mobile computing more effective ( Laptop batteries ).

INSIDE AN HARD DISK DRIVE

Magnetic diskDisk motor

Disk headAluminium casing

HARD DISK DRIVE FORM FACTORS

Six hard disk drive formats , two are commonly used today : 3.5” and 2.5”

5.25”8”

3.5” 2.5”

1”

As you can see hard disks come in many shapes and sizes however hard disks that are larger then 5.25” are currently not being used.

WHO INVENTED THE HARD DISK?

The hard disk drive was originally invented by an IBM team led by Rey Johnson in 1954. However since his teams invention of the technology significant improvements have been made.

IN CONCLUSION

A hard disk has revolutionised the digital age as we know it. Hard disks are the most widely used technology for storage of our information and data. Without hard disks the computer digital age we live in would not be the same.

REFERENCES

http://en.wikipedia.org/wiki/Hard_disk_drive

http://computer.howstuffworks.com/hard-disk.htm