It's a question that crops up with depressing regularity: Why don't Linux filesystems need to be defragmented?. Here's my attempt at giving a simple, non-technical answer as to why some filesystems suffer more from fragmenting than others.
Rather than simply stumble through lots of dry technical explanations, I'm opting to consider that an ASCII picture is worth a thousand words. Here, therefore, is the picture I shall be using to explain the whole thing:
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