Computer Hardware:
     • Tools, Static & Cleaning
     • Form Factor
     • PC Case & Fans
     • Motherboard
     • Processor (CPU)
     • Power Supply Unit
     • RAM
     • Hard Drive
     • Solid State Drive
     • Optical Drive
     • Floppy Disk Drive
     • Graphics Card
     • Sound Card
     • Network Card
     • Computer Monitor
     • Keyboard & Mouse
     • Laptop / Netbook
     • Building a Computer
     • Overclocking

Operating System & Backup:
     • Operating System
     • Drivers
     • Windows Tools
     • User Accounts
     • Backup
     • Windows 10

Internet & Network:
     • Internet
     • Wi-fi or Cable
     • Improve Broadband Speed
     • Network Computers

Computer Peripherals:
     • Printer
     • Scanner
     • External Hard Drive
     • USB Flash Drive

Computer Security:
     • Anti-virus
     • Anti-Spyware
     • Phishing
     • Firewall

Common PC Problems:
     • Slow Computer
     • Hardware Failure
     • Software Failure
     • Printing Problems

     • Windows Shortcuts
     • Glossary of Terms
     • HTML Colour Picker
     • Number Base Converter

How a Hard Drive works

A Hard Drive is a magnetic storage device for storing and retrieving digital information on rapidly spinning disks called platters which are coated with a magnetic material. The Hard Drive contains magnetic heads which are attached to a moving actuator arm and can read or write to the platters.

Hard Drive Drawing. The disk shaped platters on a Hard Drive are rigid as opposed to a Floppy Disk and this is what gives the Hard Disk Drive its name. A read/write head is suspended above and below each platter and the heads are attached to a moveable actuator arm. The spindle holds the platters and spins at high speed. All these components inside the Hard Drive are sealed to stop any dust from entering the mechanism.

How data is stored on a Hard Drive

When a Hard Drive is formatted (low-level) then it prepares the platter surfaces into tracks and sectors. Each sector can store a fixed number of bytes (usually 512 bytes). Sectors are also grouped together into clusters by the operating system.
Tracks & Sectors on a Platter. The drawing on the left represents a Hard Drive platter that has been formatted with tracks and sectors. A track can be seen coloured in yellow, a sector in blue, and a cluster in pink.

The Hard Drive can be partitioned into multiple logical storage units which allows you to use the Hard Drive as if it were several drives instead of one.

When the Hard Drive is formatted (High-level) then the 'file system' is added and a boot sector is written to the disk. The file system is used to control how information is stored and retrieved. File systems typically use directories or folders which allow the user to group files into separate collections. The Windows operating systems use FAT16, FAT32, or more recently NTFS file systems. The boot sector is written to the disk and allows the computer to automatically load a program such as the operating system.

How do i partition and format my new Hard Drive?

You should first partition a Hard Drive before it is formatted. If you intend to partion and format a Hard Drive which is to contain the operating system then you will need your operating system disk and a working Optical Drive. Boot up your computer to the CMOS setup page and make sure the 'boot sequence' is set to boot from your CD/DVD Drive before your Hard Drive. Put your operating system disk in your Optical Drive and exit the CMOS setup page. Just follow the on screen instructions to partition, format, and install your operating system.

If you have added a Hard Drive which is additional to your main Hard Drive (which contains the operation system) then you can use 'Disk Management' (Windows operating system). To run the 'Disk Management' program then press the Windows Key + 'R' and enter 'diskmgmt.msc' into the text box and click OK. This program will list all your Hard Drives and allow you to partition and format your new Hard Drive. Details of using Disk Management can be found here.

It should be mentioned that if you partition or format a Hard Drive that contains any files then they will be deleted. You can however buy third-party disk-management software that will allow you to add partitions without any loss of files.

Newer computers now use UEFI instead of the older BIOS. UEFI computers usually use a new partition style called GPT (GUID Partition Table) on its storage device (Hard Drive etc) but can also use the older MBR (Master Boot Record) partition style by selecting 'Legacy Mode' in the UEFI (CMOS setup page).


A Hard Drive's files will become fragmented over time as you save, change, or delete files which means that the program or file you want to open may be chopped and stored in multiple locations on the disk. This makes retrieving the file slower as the Hard Drive's heads have further to travel to find all of the file. The Window's operating system provides a program to defrag the Hard Drive by rearranging files stored on the disk to occupy contiguous storage locations.

MENU (Hard Drive):
1. Hard Drive 2. Upgrading Hard Drive 3. How a Hard Drive works