<s>
JkDefrag	B-Application
is	O
a	O
free	O
open-source	B-Application
disk	B-Application
defragmenting	I-Application
utility	B-Application
computer	B-Application
program	I-Application
for	O
Windows	B-Application
.	O
</s>
<s>
It	O
was	O
developed	O
by	O
Jeroen	O
Kessels	O
(	O
initials	O
"	O
JK	O
"	O
,	O
hence	O
the	O
name	O
)	O
beginning	O
in	O
2004	O
and	O
was	O
released	O
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
.	O
</s>
<s>
Since	O
version	O
4	O
of	O
2008	O
,	O
much	O
changed	O
from	O
previous	O
versions	O
,	O
JkDefrag	B-Application
was	O
renamed	O
MyDefrag	B-Application
by	O
its	O
developer	O
;	O
earlier	O
JkDefrag	B-Application
versions	O
continued	O
to	O
be	O
available	O
.	O
</s>
<s>
MyDefrag	B-Application
,	O
which	O
was	O
closed	B-Application
source	I-Application
freeware	B-License
,	O
was	O
discontinued	O
,	O
with	O
the	O
last	O
version	O
being	O
v4.3.1	O
,	O
file	O
date	O
21	O
May	O
2010	O
;	O
for	O
several	O
years	O
the	O
MyDefrag	B-Application
website	O
has	O
been	O
a	O
redirect	O
to	O
the	O
still-existing	O
JkDefrag	B-Application
site	O
,	O
but	O
links	O
to	O
downloadable	O
JKdefrag	B-Application
files	O
are	O
dead	O
.	O
</s>
<s>
JkDefrag	B-Application
has	O
many	O
options	O
.	O
</s>
<s>
JkDefrag	B-Application
characteristics	O
:	O
</s>
<s>
Both	O
command-line	B-Application
&	O
graphical	O
executable	O
programs	O
,	O
about	O
500k	O
bytes	O
total	O
size	O
;	O
</s>
<s>
A	O
range	O
of	O
command	B-Application
line	I-Application
interface	I-Application
options	O
,	O
allowing	O
for	O
scheduled	O
defragmentation	B-Application
with	O
administrator	O
scripts	O
;	O
</s>
<s>
No	O
need	O
for	O
installation	O
;	O
runs	O
with	O
default	O
options	O
by	O
opening	O
JkDefrag.exe	O
;	O
</s>
<s>
Screensaver	B-General_Concept
defragmentation	B-Application
,	O
with	O
the	O
option	O
to	O
run	O
another	O
screensaver	B-General_Concept
when	O
done	O
;	O
</s>
<s>
Source	O
code	O
(	O
Microsoft	O
Visual	O
C++	O
2005	O
for	O
32-bit	O
version	O
and	O
Microsoft	O
Visual	O
C++	O
2008	O
for	O
64-bit	O
version	O
)	O
available	O
;	O
</s>
<s>
A	O
DLL	O
library	B-Library
(	O
for	O
use	O
in	O
programming	O
)	O
licensed	O
using	O
the	O
LGPL	B-Application
;	O
</s>
<s>
Support	O
for	O
64-bit	O
versions	O
of	O
Windows	B-Application
XP	I-Application
and	O
Vista	B-Application
with	O
native	O
x64	O
binaries	O
;	O
</s>
<s>
JkDefrag	B-Application
runs	O
on	O
the	O
Windows	O
2000/XP/2003/Vista	O
Operating	O
Systems	O
,	O
and	O
defragments	B-Application
both	O
FAT	B-Application
and	O
NTFS	B-Application
filesystems	O
.	O
</s>
<s>
It	O
uses	O
the	O
standard	O
Windows	B-Application
defragmentation	B-Application
API	B-General_Concept
.	O
</s>
<s>
Because	O
of	O
that	O
,	O
it	O
could	O
technically	O
even	O
be	O
used	O
on	O
operating	B-General_Concept
systems	I-General_Concept
up	O
to	O
Windows	B-Application
11	O
.	O
</s>
<s>
However	O
such	O
use	O
would	O
be	O
completely	O
unsupported	O
and	O
might	O
bear	O
the	O
risk	O
of	O
data	O
loss	O
or	O
a	O
corrupt	O
OS	B-General_Concept
or	O
other	O
severe	O
problems	O
.	O
</s>
<s>
There	O
are	O
several	O
graphical	B-Application
user	I-Application
interface	I-Application
utilities	O
designed	O
to	O
work	O
with	O
JkDefrag	B-Application
:	O
</s>
<s>
JKDefrag	B-Application
Option	O
GUI	B-Application
by	O
Emiel	O
Wieldraaijer	O
includes	O
support	O
for	O
26	O
languages	O
,	O
and	O
has	O
support	O
for	O
BartPE	B-Application
and	O
U3	O
implementations	O
.	O
</s>
<s>
ScanDefrag	O
supports	O
JkDefrag	B-Application
and	O
allows	O
it	O
to	O
run	O
during	O
Windows	B-Application
startup	O
.	O
</s>
<s>
The	O
only	O
other	O
Windows-based	O
defrag	B-Application
program	O
with	O
a	O
GNU	B-License
GPL	I-License
is	O
UltraDefrag	B-Language
before	O
version	O
8	O
.	O
</s>
