<s>
IBM	O
's	O
Hierarchical	B-Application
File	I-Application
System	I-Application
(	O
HFS	B-Application
)	O
is	O
a	O
POSIX-style	O
hierarchical	B-Application
file	I-Application
system	I-Application
for	O
the	O
MVS/ESA/SP	O
through	O
z/OS	B-Application
operating	O
systems	O
.	O
</s>
<s>
IBM	O
introduced	O
HFS	B-Application
on	O
February	O
9	O
,	O
1993	O
in	O
MVS/ESA	O
System	O
Product	O
Version	O
4	O
Release	O
3	O
OpenEdition	B-Operating_System
with	O
DFSMS/MVS	O
Version	O
1	O
Release	O
2	O
for	O
3090	B-Device
mainframes	O
.	O
</s>
<s>
On	O
April	O
6	O
,	O
1994	O
,	O
IBM	O
introduced	O
MVS/ESA	O
System	O
Product	O
(	O
MVS/ESA	O
SP	O
)	O
Version	O
5	O
Release	O
1	O
,	O
which	O
included	O
MVS	O
OpenEdition	B-Operating_System
(	O
MVS-OE	O
)	O
with	O
HFS	B-Application
as	O
a	O
standard	O
component	O
.	O
</s>
<s>
IBM	O
continued	O
providing	O
HFS	B-Application
through	O
z/OS	B-Application
2.4	O
for	O
z	B-Device
System	I-Device
mainframes	O
.	O
</s>
<s>
IBM	O
functionally	O
stabilized	O
HFS	B-Application
starting	O
with	O
z/OS	B-Application
1.7	O
,	O
in	O
2005	O
.	O
</s>
<s>
The	O
z/OS	B-Application
File	I-Application
System	I-Application
(	O
zFS	B-Application
)	O
was	O
released	O
as	O
the	O
higher	O
performance	O
successor	O
to	O
HFS	B-Application
in	O
1995	O
,	O
and	O
IBM	O
recommended	O
migration	O
from	O
HFS	B-Application
to	O
zFS	B-Application
.	O
</s>
<s>
Following	O
the	O
release	O
of	O
zFS	B-Application
,	O
z/OS	B-Application
releases	O
included	O
a	O
tool	O
,	O
BPXWH2Z	O
,	O
to	O
convert	O
HFS	B-Application
to	O
zFS	B-Application
.	O
</s>
<s>
IBM	O
dropped	O
the	O
use	O
of	O
HFS	B-Application
in	O
z/OS	B-Application
2.5	O
,	O
in	O
2021	O
.	O
</s>
