Lessons
|
Defragging
What is it?
Click to watch
Defragmentation, also known as "defragging," is a process that takes all the parts of a file scattered across a computer's hard drive and rejoins the multiple pieces of each file into one area.
To you and me, a file on your disk is a single thing. You open it, you work on it, you save it. We might compare it to say a book. To your computer, however, a file is a lot more like a bunch of pages in that book that it has to keep track of individually. Imagine that you have a book, but that the pages are randomly scattered throughout your house. You have a list of where each page is, so when you want to read your book you go find page 1, then you look on the list for page 2 and go to that, then look up page 3, and so on. In order to read your book in order, you're racing around the house like crazy because the pages are all over. That's a fragmented file. The parts that make up the file are scattered all over the disk. The result is that when you open the file, Windows has to race all over the disk to get the whole thing. That takes time. Defragmentation is nothing more than pulling all the pages/sectors together in order, so that they're close to each other. In a perfect defragmented disk, the parts of each file would be in an orderly sequence one right after the other, just like the pages in a book. Why it happens?
Fragmentation happens because files on the disk are constantly changing; being created, deleted, grown, or shrunk in size. And all of that happens in a fairly random order.
For example purposes, let's say we have a very tiny disk that has exactly 12 parts and on this disk, we've created three files: file1, file2 and file3: File 1 takes up two sectors, file 2 takes two, and file 3 takes up five parts on the disk, leaving three parts free at the end.
We now delete file 2: As you can see, that leaves a "hole" of two empty parts between the remaining files 1 and 3.
Now, we'll create a new file, file 4, which is four parts long: The only way to save file 4 is to split it into two fragments: two parts in part "(a)" and two parts in part "(b)".
How to Defrag?
Click for larger image
Defragging a computer is easy!
|