When is disk defragmentation needed

Defragmenting does not change any of the files' contents, and does not affect anything you see on the screen documents, shortcuts on the desktop, etc. If you'd like to learn how to defragment manually, click here. Skip to main content. You are here Documentation » How Defragmenting Works.

How Defragmenting Works When a program saves a file on a disk, it puts the file into an empty space on the disk. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights.

Measure content performance. Develop and improve products. List of Partners vendors. Keith Ward. Keith Ward is a former Lifewire writer with over 25 years' experience writing about Microsoft products and creating and Windows tutorials. Updated on July 13, Tweet Share Email. Dear Defragging, "Defrag" is short for "defragment," which is a maintenance task required by your hard drives.

Most hard drives have spinning platters, with data stored in different places around that platter. When your computer writes data to your drive, it does so in "blocks" that are ordered sequentially from one side of the drive's platter to the other. Fragmentation happens when those files get split between blocks that are far away from each other. The hard drive then takes longer to read that file because the read head has to "visit" multiple spots on the platter.

Defragmentation puts those blocks back in sequential order, so your drive head doesn't have to run around the entire platter to read a single file.

Image by XZise. Relax and be free from anxiety Take back good sleep and help alleviate pain. Fragmentation doesn't cause your computer to slow down as much as it used to—at least not until it's very fragmented—but the simple answer is yes, you should still defragment your computer.

However, your computer may already do it automatically. Defragmenting a SSD will likely not improve performance and cause the drive to wear out faster. SSDs, or flash hard drives, do not physically move a controller arm to read data stored on a physical disk and instead recall information stored on flash memory. Because of the way SSDs operate, the seek time becomes negligible, so a fragmented file won't make a difference. Additionally, many SSDs use algorithms that deliberately spread data over flash memory chips that only make sense to the SSD's controller.

Since the computer doesn't process the SSD data arrangement algorithms, the data is shuffled around and not actually defragmented. Windows can run hard drive defragmentation in the background so that it's unnoticeable. You can run on-demand defragmentation or adjust background defragmentation frequency with the "Optimize Drives" program.