The Hard Disk

From throwing our unnecessary files, to defragmenting, from partitions to formats-learn how to keep your hard disk in top shape

The hard disk is the place where all your programs and data are stored. If the hard disk Stops working you could end up losing all your data. What we'll do here is take you on. A quick tour of the different things you need to know about it, so you can keep it working smoothly.

What is the hard disk?

The hard disk is a magnetic mass storage device installed in special bays within the system unit. The hard disk could do compared to a large cupboard having several shelves

With different items being neatly arranged and stored on each self. The hard disk stored all the data you need to store on your PC-the operating system (for example, Windows),

software program (for example an office suit), Business or household applications and data, games, e-mail message, address books and so on.

A hard disk off the assembly line is just a mass of magnetic media. The magnetic surface of the hard disk has to be structured into specific areas where data can be stored properly, a process known as formatting. When you buy a new computer, the system comes with a formatted hard disk.

A hard disk needs to be divided into partitions before it can be used. The hard disk on a newly purchased computer comes configured with a single large partitions, the primary partition (C: in My Computer) and an extended partition, which may be further subdivided into logical partitions (D: E: and so on in My computer) if required. Partitioning makes the storage of data more efficient and reduces the access time to retrieve data.

The storage capacity of hard disk has increased by leaps and bounds since IBM XT's first 10 MB hard disk. Nowadays, 10GB is the entry level and 17 GB is common. The hard disk communicates with a PC's motherboard through an expansion card or a disk interface card.

How does it wok?

The disk is formatted to divide its magnetic surface into concentric circular paths called tracks (these are like the grooves on a phonograph record) and wedge-shaped slices called sectors. Data is stored in the form of a file or groups of disk sector called clusters. A disk drive locates data by moving its magnetic read-write head to specific track within a specific sector.

When a new file is created in a freshly formatted hard disk, it is assigned cluster numbers in a sequential order. If the file is expanded, then the first available clusters are assigned. When file is deleted, their cluster numbers are simply marked as available. Over course of time, when files grow in size to require additional cluster or are deleted, the perfectly ordered sequence of clusters gets disturbed, a process known as fragmentation.

Partitioning the hard disk

Partitioning divides a large hard disk into smaller virtual-not physical-hard disk or partitions, leading to an efficient utilization of space and boosting your PC's performance. Partitioning could be very useful in following circumstances:

1-One PC, several users-If several persons have to work on the same PC, partitions could be assigned for each of them so that each person has his or her own "working space." This could be useful in Home setting too, where you could have separate partitions for your spouse, children's games, Business applications and data and so on.

2-Work on multiple operating systems-You may want to work on more than one operating system on your PC, for example Win98, Linux and Windows95. (Maybe you have applications that work perfectly in Win95 but suddenly crashed in Win98). You can keep these various operating systems safely on the same hard disk by installing them in separate partitions.

Partitioning Tools There're several partitioning tools available for your hard drive. Two of the most popular ones are:

1-PartitionMagic Version 4.o for Windows95 and 98-Partition Magic, from Power Quest is a useful and powerful partitioning program. It effortlessly creates, moves, converts