NTFS stands for NT File System, presumably. (I've no idea what NT
stands for. Certain jokesters have their own opinions, mine among
them.)

Yeah, yeah.

And NT stands for New Technology. It was written as a "Windows Like"
operating system to run on hardware stuff by Sun Micro and the old DEC which
used UNIX. At some point Micro$oft is to make the NT and Windows
essentially the same operating system.



A file system is a method by which the unorganized data in
a disk partition -- basically, a very long chain of blocks,
or perhaps a mapping from an integer (the logical block
address) to a fixed-size chunk of data (the block) -- can
be organized into something more appetizing to humans:
files, directories, symbolic links, or in Microsoft
parlance (perhaps), documents, folders, and shortcuts.
DOS 1.0's FAT filesystem didn't even have directories
(that was added in 1.1 or 2.0; I forget which).

Well, you lost me again. The directory is supposed to point to the entry
in the FAT corresponding to the first "allocation unit" of the file. From
my old memoery, the Intel development system just had a fixed directory.
Directory entry #1 was the first allocation unit, etc. Longer files were
accomodated by "chaining" directories.


NTFS is
fairly sophisticated; it has, among other things:

- per-file locking (to the intense annoyance of UNIX and Linux
programmers, this appears to be on by default)

Well, WTF does it "lock?'

- resource streams a la Macintosh (which aren't apparently used yet?)

That doesn't help.

- Access Control Lists

OK.

- Unicode support

Which means ...

- Case-preserving filenames

OK

- a master file table, which is where the small files live

Huh?

- sparse files (files with "holes" in their blocklists -- a
useful capability in some contexts related to databases, AIUI)

Neat!

- short file name capability for DOS backwards compatibility

OK

- hidden files

Old stuff.

- support for running a defragmenter while the volume is mounted.
(Don't ask.)

Well, I understand was the defragmenter does in a FAT system but since I
still don't understand how files are stored I can't understand how that are
either fragmented or defragmented.


There are a few other capabilities but I'd have to look.

OK



If you really do want to look it up, you can try
the Linux source code -- an NTFS implementation
is in the kernel under /usr/src/linux/fs/ntfs or
/usr/src/linux/Documentation/filesystems/ntfs.txt. It is
definitely not for the faint of heart. There should
be some documentation somewhere on Microsoft's website,
of course; again, I'd have to look.

Sorry, you have just asked me to think and work harder than I care to.