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70 votes

When was the term ‘directory’ replaced by ‘folder’?

Directory is a filesystem concept. Folder is a user-level concept. From its beginning in the 1980s, the Macintosh GUI (and possibly other GUIs before it) only talked about "folders" and ...
Nimloth's user avatar
  • 2,068
64 votes
Accepted

Who invented file extensions in file names?

The MIT Compatible Time-Sharing System (CTSS), demonstrated in 1961, had two "names" for each file, with the second telling CTSS how to process the file. This had the function of a filename ...
John Dallman's user avatar
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56 votes

Who invented file extensions in file names?

The PDP-6 multiprogramming monitor, an early operating system first delivered in 1964, used the term "filename extension" for the second name attached to a file, usually indicating the type. ...
Walter Mitty's user avatar
  • 6,138
54 votes

What exactly did the "UNFORMAT" MS-DOS command do?

If you format a drive with quick format option (FORMAT /Q), it only clears the root directory and FAT area, but before doing so, the format command stores them in unused area of the disk. This is ...
Justme's user avatar
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50 votes
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Origin of the 8.3 file names scheme

It was because the fairly common 6.3 scheme of the time was considered too small :-) Seriously: 8.3 wasn't a particularly onerous restriction at the time. Many PDP-11 operating systems had a 6 ...
dave's user avatar
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44 votes

Filesystems with versioning

FILES-11 on DEC minicomputers was a versioned file system -- RSX-11M, IAS (on PDP-11), VMS (on VAX, Alpha). Version numbers are very user-visible; they are part of the syntax for specifying a file. ...
dave's user avatar
  • 35.6k
42 votes

When was the term ‘directory’ replaced by ‘folder’?

TL;DR: No, 'Directories' were never replaced by 'Folders'. They are the same. The names just represent different views: Directory is the data structure holding information about files (and other ...
Raffzahn's user avatar
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41 votes

Who invented file extensions in file names?

In addition to Walter's spot on answer about the combined use of extensions and delimiting them by a dot and John's about the CTSS (*1) as origin for user defined types, it might be worth to note that ...
Raffzahn's user avatar
  • 224k
40 votes
Accepted

Why did MacOS Classic choose the colon as a path separator?

Colon was inherited from SOS for the Apple III Unlike one may assume, MacOS (1984/01) did not inherited the colon (:) from Lisa OS (1983/01), which used a hyphen (-) as path separator, but from Apple ...
Raffzahn's user avatar
  • 224k
39 votes
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What was the point of Apple Pascal having its own file system?

UCSD Pascal was a product of UCSD - The University of California at San Diego. It was not a product of Apple. UCSD Pascal was available on a number of machines, including the PDP-11, TI99/4, the BBC ...
Chenmunka's user avatar
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38 votes
Accepted

Why was the DOS clock device renamed from CLOCK into CLOCK$?

Quick partial answer: CON, LST, PRN and AUX (*1) are names inherited from CP/M, either direct form its BIOS or CP/M's main file handling utility PIP (*2). NUL was add with DOS. DOS 1.x added ...
Raffzahn's user avatar
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38 votes
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Since when does Windows support forward slash as path separator?

TL;DR: Windows did not explicitly support both, but DOS did since 2.0 The answer is rather a clear "yes but" (*1): DOS 2.0 and later supported both ways, thus all DOS functions will work ...
Raffzahn's user avatar
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35 votes
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Where was the DOS cdd utility from?

I remember CDD as a 4DOS command, which would have been available in the Norton Utilities as NDOS. JP Software’s other shells also implement CDD, so 4OS2 and 4NT users would probably recognise it too. ...
Stephen Kitt's user avatar
34 votes

How can I recover the contents from an Amiga HDD using modern Linux?

You should be able to use the Amiga hard drive directly on your Linux computer (provided it still has IDE support). Linux also understands AFFS (Amiga Fast File systems), at least once AFFS support ...
tofro's user avatar
  • 35k
34 votes

Origin of the 8.3 file names scheme

[Part of what is described here can be found on Herb Johnson's great site about CP/M history, the other is experience of 30+ years in mainframe procedure] CP/M was, Dave explains, heavily influenced ...
Raffzahn's user avatar
  • 224k
32 votes
Accepted

Why does the single dot entry exist in file systems?

It simply makes sense to have a symbol that stands for the current directory. It makes sense for the symbol to be easy to type and to stand out from ordinary directory names. Dot is a pretty good ...
Walter Mitty's user avatar
  • 6,138
32 votes
Accepted

When did files start to be dated?

CTSS, a timesharing system for the IBM 7090, was putting dates on files as early as 1962. Timestamps is another story. Wikipedia
Walter Mitty's user avatar
  • 6,138
31 votes

Why did ScanDisk exist?

There are quite a few differences between the MS-DOS CHKDSK and ScanDisk, beyond the latter’s friendlier interface. ScanDisk can “repair” cross-linked files, i.e. files which end up pointing (...
Stephen Kitt's user avatar
31 votes

How did the /dev file system work in early Unix?

In 1986 (and for a few years after that still), /dev wasn’t handled by a special file system. It was generally a directory on the root file system, and its contents were largely static: a series of ...
Stephen Kitt's user avatar
31 votes

Do any FAT8 filesystem images survive?

I think I've actually found a FAT8 disk image: Toshiba T100 Personal Computer T-DISK BASIC (Version 1.0) (1982) Why I think it is FAT8: Starting near offset 0xc530, there are repeated occurrences of ...
Simon Kissane's user avatar
29 votes
Accepted

Why is MS-DOS not able to read partitions starting at logical sector 0?

This is a consequence of a buggy overflow check. Internally, MS-DOS uses logical block addressing to access file systems. Since version 4.0, MS-DOS uses 32 bits for sector addresses in order to ...
user3840170's user avatar
  • 23.1k
28 votes

When was the term ‘directory’ replaced by ‘folder’?

1984 Mac: They did mean different things The original file system of the Macintosh was called MFS (Macintosh File System). It was released with the first Macs in 1984. In this file system, "...
DrSheldon's user avatar
  • 16k
27 votes

Why did MacOS Classic choose the colon as a path separator?

I think the colon deserves to be considered the original, the one true separator character. All others are mere imitators ;-) My rationale for this is the seminal paper A General-Purpose File System ...
dave's user avatar
  • 35.6k
26 votes

When was the term ‘directory’ replaced by ‘folder’?

I believe this is a distinction without a difference. As described reasonable well in the Wikipedia article on "directory", folder is more of a way of describing the use of a directory for ...
manassehkatz-Moving 2 Codidact's user avatar
25 votes
Accepted

Slash versus backslash as directory separator – what/who caused this rift?

PC/MS-DOS 1 used the slash (/) as the command line switch indicator (like DEC's RSX11 and DG's RTOS before), so when DOS 2.0 introduced subdirectories, they did need a new one. Backslash (\) came ...
Raffzahn's user avatar
  • 224k
25 votes

What was the point of Apple Pascal having its own file system?

UCSD Pascal was developed prior to the Apple II, during the 70's in San Diego, using PDP-11 class machines with a 512-byte block disk structure. In the process of porting it to microcomputers, often (...
Raffzahn's user avatar
  • 224k
25 votes

Filesystems with versioning

There were quite a few operating systems that had file versioning in the same era as unix. Many file systems that we are familiar with today just have some components of a file name, such as: Name....
Brian Tompsett - 汤莱恩's user avatar
25 votes

Why did MacOS Classic choose the colon as a path separator?

The original Macintosh File System did not support directories. But the Mac did support multiple floppy drives from the start, and colon : was used in fairly standard fashion as a drive prefix ...
RETRAC's user avatar
  • 13.7k
25 votes

Why was the DOS clock device renamed from CLOCK into CLOCK$?

As Raffzahn explains, the clock device driver was added in DOS 2.0. CON, AUX, etc. were device names already present in DOS 1.0, some of them even earlier in CP/M; these names couldn’t be changed to ...
Stephen Kitt's user avatar
25 votes

Why does the FAT file system have separate ‘hidden’ and ‘system’ attributes?

The attributes are documented in The MS-DOS Encyclopedia as follows: The hidden bit (bit 1) is set to 1 to indicate that the entry is to be skipped in normal directory searches — that is, in ...
Stephen Kitt's user avatar

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