What is the difference between tracks and sectors

The concept of cylinders is important, since cross-platter information in the same cylinder can be accessed without having to move the heads.

Drives use a technique called zoned-bit recording in which tracks on the outside of the disk contain more sectors than those on the inside.

The tracks, stacked on top of each other form a cylinder. This scheme is slowly being eliminated with modern hard drives. All new disks use a translation factor to make their actual hardware layout appear continuous, as this is the way that operating systems from Windows 95 onward like to work. To the operating system of a computer, tracks are logical rather than physical in structure, and are established when the disk is low-level formatted. Tracks are numbered, starting at 0 the outermost edge of the disk , and going up to the highest numbered track, typically , close to the center.

Similarly, there are 1, cylinders numbered from 0 to on a hard disk. The stack of platters rotate at a constant speed. The drive head, while positioned close to the center of the disk reads from a surface that is passing by more slowly than the surface at the outer edges of the disk.

To compensate for this physical difference, tracks near the outside of the disk are less-densely populated with data than the tracks near the center of the disk.

The result of the different data density is that the same amount of data can be read over the same period of time, from any drive head position. The disk space is filled with data according to a standard plan. One side of one platter contains space reserved for hardware track-positioning information and is not available to the operating system. Thus, a disk assembly containing two platters has three sides available for data.

Track-positioning data is written to the disk during assembly at the factory. Jan 22 AM. Roshna M answered on January 24, Do you need an answer to a question different from the above? Ask your question! We want to correct this solution. Tell us more. Was the final answer of the question wrong? Were the solution steps not detailed enough? These areas are called partitions. You can have a single partition that contains all the storage space on the drive or divide the space into several different partitions.

If you want to run more than one operating system on your machine, you can even create partitions that have different file systems. Anyway, you need at least one partition on the drive and, if you have more than one partition, the formatting process will cause them to be displayed as separate drives by your operating system — for example, in Windows Explorer or Finder on a Mac.

So it usually needs special tools to get it back. In that case, you would want to reformat the disk or partition for the new operating system. As a last resort, reformatting a disk can also be a way of removing viruses from the computer, or fixing other errors. A disk track is too large to manage the data effectively as a single storage unit. An individual disk track can store more than a megabyte of data, which would be very inefficient for storing small files.

So, as part of the formatting process, tracks are divided into several numbered, equal divisions known as sectors. Almost all file systems create sectors that can hold bytes of data. The sectors are grouped together in clusters. So a cluster is a larger unit of memory whose size depends on the particular file system being used.

A cluster always consists of one or more consecutive sectors, but typically there are four or eight or some other power of two sectors in a cluster. When a file is written to the hard disk, it always takes up a whole number of clusters. This was the case on older hard disk drives, but it meant that the sectors on the outside of the disk had a larger area than those closer to the centre, which meant that they held fewer bits per unit area, and were less efficient at storing data than the inner sectors.

Given that a sector is bytes in size, how many bytes of storage are there in a cluster composed of four sectors? It is the area of the hard disk that is used as an index of every cluster on the disk and records whether a cluster is being used or not.