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Most files I see and use end in .something, where the .something is often 3 characters. I know that some file extentions are shorter, like .py or .r, but I have never seen one longer than .exe or .jpg

I know from this FAQ that they can be up to 260 characters including the file's name.

Why is the standard 3 characters?

james12802
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    Extensions longer than 3 characters *do* exist: `.docx`, `.xlsx`, and `.pptx` since MS Office 2007, for instance. There's also `.jpeg` (same as `.jpg`, but with 4 chars instead of 3), `.flac`, `.info`, `.java`, `.json`, `.html`, `.webm`, and more. – Nolonar Aug 19 '15 at 13:14
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    Also, the now very common `.torrent` and one of my favorites, VirtualBox's `.vbox-extpack` – JaredS Jun 12 '20 at 13:03

1 Answers1

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Because back in the old days of 8-bit micros, when memory and disk space were both hugely more expensive than they are today, most operating systems used a so-called 8.3 file naming system (8 characters for the filename, and 3 for the extension).

r3mainer
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