What are tracks and sectors on a hard disk?
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View Discussion Show Improve Article Save Article View Discussion Improve Article Save Article A hard disk is a memory storage device that looks like this:  The disk is divided into tracks. Each track is further divided into sectors. The point to be noted here is that outer tracks are bigger in size than the inner tracks but they contain the same number of sectors and have equal storage capacity. This is because the storage density is high in sectors of the inner tracks whereas the bits are sparsely arranged in sectors of the outer tracks. Some space of every sector is used for formatting. So, the actual capacity of a sector is less than the given capacity. Read-Write(R-W) head moves over the rotating hard disk. It is this Read-Write head that performs all the read and writes operations on the disk and hence, the position of the R-W head is a major concern. To perform a read or write operation on a memory location, we need to place the R-W head over that position. Some important terms must be noted here:
Note: Average Rotational latency is mostly 1/2*(Rotational latency). In questions, if the seek time and controller time are not mentioned, take them to be zero. If the amount of data to be transferred is not given, assume that no data is being transferred. Otherwise, calculate the time taken to transfer the given amount of data. The average rotational latency is taken when the current position of the R-W head is not given. Because the R-W may be already present at the desired position or it might take a whole rotation to get the desired sector under the R-W head. But, if the current position of the R-W head is given then the rotational latency must be calculated. Example –
in order to get maintain the organized storage and retrieval of data the platters are organized into specific structures. These specific structures include tracks, sectors, and clusters. TRACKS: Each platter is broken into thousands of tightly packed concentric circles, known as tracks. These tracks resemble the structure of annual rings of a tree. All the information stored on the hard disk is recorded in tracks. Starting from zero at the outer side of the platter, the number of tracks goes on increasing to the inner side. Each track can hold a large amount of data counting to thousands of bytes. SECTORS:Each track is further broken down into smaller units called sectors. As sector is the basic unit of data storage on a hard disk. A single track typically can have thousands of sectors and each sector can hold more than 512 bytes of data. A few additional bytes are required for control structures and error detection and correction. CLUSTERS:Sectors are often grouped together to form Clusters. --------------- Heads Every hard drive consists of platters and read-write heads. If a drive has four platters, it usually has eight read-write heads, one on the top and bottom of each platter. The head value is the number of read-write heads in the drive. Cylinders Each platter is divided into tracks. The cylinder value is the number of tracks on one side of each platter. There are the same number of cylinders on each side of each platter. The sector value is the number of sectors in each cylinder (or track), each sector consisting of (normally) 512 bytes. . What are tracks in hard disk?A disk drive track is a circular path on the surface of a disk or diskette on which information is magnetically recorded and from which recorded information is read.
What are tracks sectors and cylinders in hard disk drive?Each surface is divided into tracks (and sectors) in the same way. This means that when the head for one surface is on a track, the heads for the other surfaces are also on the corresponding tracks. All the corresponding tracks taken together are called a cylinder.
How many sectors are in a track?Of course, all modern drives use 63 sectors per track.
How many tracks are there in hard disk?In a figure below, cylinder 0 is the four tracks at the outermost edge of the sides of the platters. If the disk has 1024 cylinders (which would be numbered 0-1023), cylinder 1023 consists of all of the tracks at the innermost edge of each side.
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