<s>
PKPASS	B-General_Concept
is	O
a	O
file	O
format	O
,	O
used	O
for	O
storage	O
and	O
exchange	O
of	O
digital	O
passes	O
,	O
developed	O
by	O
Apple	O
for	O
its	O
Wallet	B-Operating_System
application	O
.	O
</s>
<s>
Also	O
called	O
"	O
PassBook	B-Operating_System
"	O
,	O
it	O
's	O
intended	O
to	O
represent	O
information	O
that	O
"	O
might	O
otherwise	O
be	O
printed	O
on	O
small	O
pieces	O
of	O
paper	O
or	O
plastic	O
"	O
like	O
boarding	O
passes	O
,	O
membership	O
cards	O
,	O
coupons	O
,	O
certificates	O
,	O
etc	O
.	O
</s>
<s>
The	O
format	O
specification	O
has	O
been	O
published	O
online	O
and	O
this	O
allowed	O
for	O
compatible	O
implementations	O
to	O
be	O
developed	O
for	O
other	O
platforms	O
like	O
Android	B-Application
and	O
Windows	B-Application
.	O
</s>
<s>
The	O
file	O
is	O
a	O
ZIP	B-General_Concept
archive	I-General_Concept
with	O
a	O
filename	O
extension	O
.pkpass	B-General_Concept
containing	O
a	O
set	O
of	O
digitally	O
signed	O
files	O
describing	O
the	O
digital	O
pass	O
.	O
</s>
<s>
Multiple	O
.pkpass	B-General_Concept
files	O
can	O
be	O
further	O
combined	O
into	O
a	O
single	O
ZIP	B-General_Concept
archive	I-General_Concept
with	O
an	O
extension	O
of	O
.pkpasses	B-General_Concept
in	O
order	O
to	O
combine	O
several	O
digital	O
passes	O
for	O
ease	O
of	O
distribution	O
.	O
</s>
<s>
The	O
file	O
contents	O
of	O
a	O
sample	O
PKPASS	B-General_Concept
file	O
might	O
look	O
like	O
this	O
:	O
</s>
<s>
The	O
file	O
pass.json	O
is	O
a	O
JSON	B-General_Concept
formatted	O
dictionary	O
describing	O
the	O
digital	O
pass	O
.	O
</s>
<s>
manifest.json	O
contains	O
a	O
JSON	B-General_Concept
dictionary	O
containing	O
SHA-1	B-Algorithm
hashes	I-Algorithm
for	O
all	O
files	O
except	O
the	O
manifest	O
itself	O
and	O
the	O
signature	O
.	O
</s>
<s>
signature	O
contains	O
a	O
PKCS	B-General_Concept
#7	I-General_Concept
signature	O
of	O
the	O
manifest	O
file	O
thus	O
effectively	O
signing	O
all	O
files	O
in	O
the	O
bundle	O
.	O
</s>
