Because it lets you know how much space is left, and it let's your computer store information more efficiently.
Defragmenting regularly also helps prevent your computer's performance from degrading. Over time, as files are added, modified and deleted from your disk, individual files can become fragmented - rather than being stored in one contiguous location on the disk, they're split into sections and stored in different parts of the disk. This adversely affects performance, because the entire file can no longer be retrieved from a single location on disk. Defragmenting regularly helps to prevent this and keep your computer running smoothly.
When files are created/edited/deleted they cause gaps in your hard drive structure. When a high level of fragmentation is reached (15% and above) your system will become slower as your hard drive has to look through a structure which now has several gaps which cause slower response times. Using disk defragmentation tools allows these gaps to be closed and all your files moved into easily read blocks for your hard drive to search through in times to come.
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Defragmentation also moves the most used files to the begining of the disk for quicker access.
Its important to defrag the computer to prevent performance deterioration (like slowdowns and lags) caused by file fragmentation over time. A defrag reorganizes the fragmented files sequentially and speeds up data access.
Very very simple: Click the start button, then click on Control Panel, then click on Performance and Maintenance, finally click on Rearrange Items on Your Hard Disk
to Make Programs Run Faster. The Disk Defragmenter Screen comes up. Select the drive you want to defragment, then click the Analyse button and wait for the program to tell
you if is necessary to defragment or not. You can still override that option by clicking
the Defragment button any way.
Another Answer
In a hard disk drive, there are thin aluminum platters coated with magnetic oxides. These platters spin at high rotation rates. 7200 RPM is a common rotation speed and 5 inches is a common diameter. The platters are where the data are stored in the form of magnetic hysteresis loops in the oxide layer. The size of the hysteresis loops, the speed of the platters, and the number of platter surfaces add up to determine the drive capacity.
The hysteresis loops are written to and read from the surfaces by magnetic heads. These heads are basically horseshoe electro-magnets with miniscule gaps between the ends of the shoe. The gap size of the electro-magnets determines maximum frequency that can be recorded and the hysteresis loop size in the oxide layer. The hysteresis loops are equated to the bits of data being recorded.
The organization of the data on the surface is more physical than electrical. The surfaces are formatted which creates a series of sectors on tracks of each platter surface. When data is being written to the surfaces, each sector points to the next sector in the file and the sector the previous data came from. The scheme used to write the data to the surfaces gets complex, but after data has been written and deleted a number of times, the file structures become fragmented. This is in relation to how fast the data can be read from the surface, passed to the buffer, and then starts reading again. By this time the head is over a different location separated from the sector it just read by the physics of the surface rotation and the speed of the electronics moving the data. This new location on the surface would be the optimal place for the next sector to be located. This is what the "Defragment" program does.
Over time the files on your computer can become very scattered. Files are found on hard drives by moving a tiny arm called a head across the surface of the disk. If the files are scattered it takes longer for the head to move across the disk and consequently for your computer to find the files (this time is called the seek time). It also means that the empty space on your computer is scattered around, making it harder to find new places to put files. If you try moving or adding a large file onto a fragmented disk it has to move lots tiny files out of the way. Both of these can make your computer appear to run slower. It's not physically running any slower or faster though - it's just taking longer for it to get the data. Defragmenting pushes all of your files together so the drive head does not need to move as much and moves the empty space to the end of the drive so your computer can quickly find it.
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High levels of fragmentation tend to affect the HDD performance leading to slowdown in opening of programs and files as well as longer boot times. To reduce performance issues caused by fragmentation, its good to defragment regularly.
You don't need to but it is a good idea. It clears up some space and helps your PC run faster.
Defragging a computer defrags the hard drive disk inside your computer where all of your information is stored. This clears up any lingering junk on your drive and saves you space.
Defragmentation is the process of taking the fragments of a large file and putting them together. Defragmentation increases computer performance drastically.
Defragment the hard drive.
The same way you defragment a normal PC hard drive. Hook it up, right click the drive in My Computer, go to tools, an among, disk clean up and error checking, there should be the option to defragment it. Once your there, just click defragment.
You should defragment your drive at least once a month to keep it running smooth and clear out unneeded items.
Defragment of your hard drive on a monthly basis is one way of maintaining the hard drive.
Defragment your hard drive. Be careful though...
Defragment the hard drive.
A fragmented drive results in slow read and write operations as the files are scattered all over the hard disk. Microsoft Windows provides defragmenter utility to defragment the hard drive. Go to Start --> Programs --> Accessories --> System Tools --> Defragmenter
It is a good idea to regularly back up important files and defragment your hard drive. It will make it last longer
that all it programed to do speeds up you OS
When you add software or programs to your computer, it will have less free space available than previously. Your hard drive has a fixed capacity, and you should always leave some free space available. As you add data, you should defragment the drive from time to time.
In Windows, go to Computer or My Computer and right-click on the drive that you wish to defrag. On the context menu, select Properties. Then tab over to Tools and select defragment. If you run into trouble, then scan the drive for errors. That is found in the same place where you load Defrag. If you still have trouble, then scan and defragment in Safe Mode. Or you can install a program such as Defraggler from Piriform and use it to defrag the hard drive.
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