<s>
An	O
esoteric	O
programming	O
language	O
(	O
sometimes	O
shortened	O
to	O
esolang	O
)	O
is	O
a	B-Language
programming	I-Language
language	I-Language
designed	O
to	O
test	O
the	O
boundaries	O
of	O
computer	O
programming	O
language	O
design	O
,	O
as	O
a	O
proof	O
of	O
concept	O
,	O
as	O
software	O
art	O
,	O
as	O
a	O
hacking	O
interface	O
to	O
another	O
language	O
(	O
particularly	O
functional	B-Language
programming	I-Language
or	O
procedural	B-Application
programming	I-Application
languages	I-Application
)	O
,	O
or	O
as	O
a	O
joke	O
.	O
</s>
<s>
The	O
earliest	O
,	O
and	O
still	O
the	O
canonical	O
example	O
of	O
an	O
esoteric	O
programming	O
language	O
,	O
is	O
INTERCAL	B-Language
,	O
designed	O
in	O
1972	O
by	O
Don	O
Woods	O
and	O
James	O
M	O
.	O
Lyon	O
,	O
who	O
said	O
that	O
their	O
intention	O
was	O
to	O
create	O
a	B-Language
programming	I-Language
language	I-Language
unlike	O
any	O
with	O
which	O
they	O
were	O
familiar	O
.	O
</s>
<s>
It	O
parodied	O
elements	O
of	O
established	O
programming	O
languages	O
of	O
the	O
day	O
such	O
as	O
Fortran	B-Application
,	O
COBOL	B-Application
and	O
assembly	B-Language
language	I-Language
.	O
</s>
<s>
For	O
many	O
years	O
,	O
INTERCAL	B-Language
was	O
represented	O
only	O
by	O
paper	O
copies	O
of	O
the	O
INTERCAL	B-Language
manual	O
.	O
</s>
<s>
Its	O
revival	O
in	O
1990	O
as	O
an	O
implementation	O
in	O
C	B-Language
under	O
Unix	B-Application
stimulated	O
a	O
wave	O
of	O
interest	O
in	O
the	O
intentional	O
design	O
of	O
esoteric	O
computer	O
languages	O
.	O
</s>
<s>
In	O
1993	O
,	O
Wouter	O
van	O
Oortmerssen	O
created	O
FALSE	O
,	O
a	O
small	O
stack-oriented	B-Language
programming	I-Language
language	I-Language
with	O
syntax	O
designed	O
to	O
make	O
the	O
code	O
inherently	O
obfuscated	O
,	O
confusing	O
and	O
unreadable	O
.	O
</s>
<s>
This	O
inspired	O
Urban	O
Müller	O
to	O
create	O
an	O
even	O
smaller	O
language	O
,	O
the	O
now-infamous	O
Brainfuck	B-Language
,	O
which	O
consists	O
of	O
only	O
eight	O
recognized	O
characters	O
.	O
</s>
<s>
Along	O
with	O
Chris	O
Pressey	O
's	O
Befunge	B-Language
(	O
like	O
FALSE	O
,	O
but	O
with	O
a	O
two-dimensional	O
instruction	O
pointer	O
)	O
,	O
Brainfuck	B-Language
is	O
now	O
one	O
of	O
the	O
best-supported	O
esoteric	O
programming	O
languages	O
,	O
with	O
canonical	O
examples	O
of	O
minimal	O
Turing	O
tarpits	O
and	O
needlessly	O
obfuscated	O
language	O
features	O
.	O
</s>
<s>
Brainfuck	B-Language
is	O
related	O
to	O
the	O
P′′	B-Application
family	O
of	O
Turing	B-Architecture
machines	I-Architecture
.	O
</s>
<s>
Many	O
esoteric	O
programming	O
languages	O
,	O
such	O
as	O
brainfuck	B-Language
,	O
and	O
similar	O
,	O
use	O
single	O
characters	O
as	O
commands	O
,	O
however	O
,	O
it	O
is	O
n't	O
uncommon	O
for	O
languages	O
to	O
read	O
line	O
by	O
line	O
like	O
conventional	O
programming	O
languages	O
.	O
</s>
<s>
Conventional	O
imperative	B-Application
programming	I-Application
languages	I-Application
typically	O
allow	O
data	O
to	O
be	O
stored	O
in	O
variables	O
,	O
but	O
esoteric	O
languages	O
may	O
utilize	O
different	O
methods	O
of	O
storing	O
and	O
accessing	O
data	O
.	O
</s>
<s>
Languages	O
like	O
Brainfuck	B-Language
and	O
Malbolge	B-Language
only	O
permit	O
data	O
to	O
be	O
read	O
through	O
a	O
single	O
pointer	O
,	O
which	O
must	O
be	O
moved	O
to	O
a	O
location	O
of	O
interest	O
before	O
data	O
is	O
read	O
.	O
</s>
<s>
Others	O
,	O
like	O
Befunge	B-Language
and	O
Shakespeare	B-Language
,	O
utilize	O
one	O
or	O
more	O
stacks	B-Application
to	O
hold	O
data	O
,	O
leading	O
to	O
a	O
manner	O
of	O
execution	O
akin	O
to	O
Reverse	O
Polish	O
notation	O
.	O
</s>
<s>
Finally	O
,	O
there	O
are	O
languages	O
which	O
explore	O
alternative	O
forms	O
of	O
number	O
representation	O
:	O
the	O
Brainfuck	B-Language
variant	O
Boolfuck	O
only	O
permits	O
operations	O
on	O
single	O
bits	O
,	O
while	O
Malbolge	B-Language
and	O
INTERCAL	B-Language
variant	O
TriINTERCAL	O
replace	O
bits	O
altogether	O
with	O
a	O
base	B-Algorithm
3	I-Algorithm
ternary	B-Algorithm
system	O
.	O
</s>
<s>
Some	O
languages	O
,	O
such	O
as	O
Befunge	B-Language
and	O
Piet	B-Language
,	O
represent	O
programs	O
in	O
two	O
or	O
more	O
dimensions	O
,	O
with	O
program	O
control	O
moving	O
around	O
in	O
multiple	O
possible	O
directions	O
through	O
the	O
program	O
.	O
</s>
<s>
Shakespeare	B-Language
achieves	O
this	O
by	O
making	O
all	O
programs	O
resemble	O
Shakespearian	O
plays	O
.	O
</s>
<s>
The	O
purpose	O
of	O
this	O
may	O
be	O
to	O
provide	O
an	O
interesting	O
puzzle	O
or	O
challenge	O
for	O
program	O
writers	O
:	O
Malbolge	B-Language
for	O
instance	O
was	O
explicitly	O
designed	O
to	O
be	O
challenging	O
,	O
and	O
so	O
it	O
has	O
features	O
like	O
self-modifying	B-Application
code	I-Application
and	O
highly	O
counterintuitive	O
operations	O
.	O
</s>
<s>
Brainfuck	B-Language
is	O
committed	O
to	O
the	O
idea	O
of	O
a	O
minimalist	O
instruction	O
set	O
,	O
so	O
even	O
though	O
its	O
instructions	O
are	O
straightforward	O
in	O
principle	O
,	O
the	O
code	O
that	O
arises	O
is	O
difficult	O
for	O
a	O
human	O
to	O
read	O
.	O
</s>
<s>
INTERCAL	B-Language
's	O
difficulty	O
arises	O
as	O
a	O
result	O
of	O
the	O
choice	O
to	O
avoid	O
operations	O
used	O
in	O
any	O
other	O
programming	O
language	O
,	O
which	O
stems	O
from	O
its	O
origin	O
as	O
a	O
parody	O
of	O
other	O
languages	O
.	O
</s>
<s>
For	O
instance	O
,	O
the	O
first	O
esoteric	O
language	O
INTERCAL	B-Language
began	O
as	O
a	O
spoof	O
of	O
languages	O
used	O
in	O
the	O
1960	O
's	O
,	O
such	O
as	O
APL	B-Language
,	O
Fortran	B-Application
,	O
and	O
COBOL	B-Application
.	O
</s>
<s>
INTERCAL	B-Language
's	O
rules	O
appear	O
to	O
be	O
the	O
inverse	O
of	O
rules	O
in	O
these	O
other	O
languages	O
.	O
</s>
<s>
Shakespeare	B-Language
can	O
be	O
viewed	O
as	O
spoofing	O
the	O
structure	O
of	O
Shakespearean	O
plays	O
,	O
for	O
instance	O
.	O
</s>
<s>
is	O
a	O
parody	O
of	O
Brainfuck	B-Language
,	O
where	O
Brainfuck	B-Language
's	O
8	O
commands	O
are	O
replaced	O
by	O
various	O
orangutang	O
sounds	O
like	O
"	O
Ook	O
.	O
</s>
<s>
Befunge	B-Language
allows	O
the	O
instruction	O
pointer	O
to	O
roam	O
in	O
multiple	O
dimensions	O
through	O
the	O
code	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
following	O
program	O
displays	O
"	O
Hello	O
World	O
"	O
by	O
pushing	O
the	O
characters	O
in	O
reverse	O
order	O
onto	O
the	O
stack	B-Application
,	O
then	O
printing	O
the	O
characters	O
in	O
a	O
loop	O
which	O
circulates	O
clockwise	O
through	O
the	O
instructions	O
>	O
,	O
:	O
,	O
v	O
,	O
_	O
,	O
,,	O
and	O
^	O
.	O
</s>
<s>
There	O
are	O
many	O
versions	O
of	O
Befunge	B-Language
,	O
the	O
most	O
common	O
being	O
Befunge-93	B-Language
.	O
</s>
<s>
Binary	B-Application
lambda	I-Application
calculus	I-Application
is	O
designed	O
from	O
an	O
algorithmic	O
information	O
theory	O
perspective	O
to	O
allow	O
for	O
the	O
densest	O
possible	O
code	O
with	O
the	O
most	O
minimal	O
means	O
,	O
featuring	O
a	O
29-byte	O
self	O
interpreter	O
,	O
a	O
21-byte	O
prime	O
number	O
sieve	O
,	O
and	O
a	O
112-byte	O
Brainfuck	B-Language
interpreter	O
.	O
</s>
<s>
Brainfuck	B-Language
is	O
designed	O
for	O
extreme	O
minimalism	O
and	O
leads	O
to	O
obfuscated	O
code	O
,	O
with	O
programs	O
containing	O
only	O
eight	O
distinct	O
characters	O
.	O
</s>
<s>
The	O
compiler	O
interprets	O
the	O
amount	O
of	O
"	O
chickens	O
"	O
on	O
a	O
line	O
as	O
an	O
opcode	O
instruction	O
which	O
it	O
uses	O
to	O
manipulate	O
data	O
on	O
a	O
stack	B-Application
.	O
</s>
<s>
Chef	O
is	O
a	O
stack-oriented	B-Language
programming	I-Language
language	I-Language
created	O
by	O
David	O
Morgan-Mar	O
,	O
designed	O
to	O
make	O
programs	O
look	O
like	O
cooking	O
recipes	O
.	O
</s>
<s>
Programs	O
consist	O
of	O
a	O
title	O
,	O
a	O
list	O
of	O
variables	O
and	O
their	O
data	O
values	O
,	O
and	O
a	O
list	O
of	O
stack	B-Application
manipulation	O
instructions	O
.	O
</s>
<s>
A	O
FRACTRAN	B-Application
program	O
is	O
an	O
ordered	O
list	O
of	O
positive	O
fractions	O
together	O
with	O
an	O
initial	O
positive	O
integer	O
input	O
.	O
</s>
<s>
FRACTRAN	B-Application
was	O
invented	O
by	O
mathematician	O
John	O
Conway	O
.	O
</s>
<s>
Programs	O
in	O
GolfScript	O
,	O
a	O
language	O
created	O
for	O
code	O
golf	O
,	O
consist	O
of	O
lists	O
of	O
items	O
,	O
each	O
of	O
which	O
is	O
pushed	O
onto	O
the	O
stack	B-Application
as	O
it	O
is	O
encountered	O
,	O
with	O
the	O
exception	O
of	O
variables	O
which	O
have	O
code	O
blocks	O
as	O
their	O
value	O
,	O
in	O
which	O
case	O
the	O
code	O
is	O
executed	O
.	O
</s>
<s>
INTERCAL	B-Language
,	O
short	O
for	O
"	O
Compiler	B-Language
Language	I-Language
With	I-Language
No	I-Language
Pronounceable	I-Language
Acronym	I-Language
"	O
,	O
was	O
created	O
in	O
1972	O
as	O
a	O
parody	O
to	O
satirize	O
aspects	O
of	O
the	O
various	O
programming	O
languages	O
at	O
the	O
time	O
.	O
</s>
<s>
JSFuck	B-Language
is	O
an	O
esoteric	O
programming	O
style	O
of	O
JavaScript	B-Language
,	O
where	O
code	O
is	O
written	O
using	O
only	O
six	O
characters	O
:	O
[	O
,	O
]	O
,	O
(	O
,	O
)	O
,	O
!,	O
and	O
+	O
.	O
</s>
<s>
Unlike	O
Brainfuck	B-Language
,	O
which	O
requires	O
its	O
own	O
compiler	O
or	O
interpreter	O
,	O
JSFuck	B-Language
is	O
valid	O
JavaScript	B-Language
code	O
,	O
meaning	O
JSFuck	B-Language
programs	O
can	O
be	O
run	O
in	O
any	O
web	B-Application
browser	I-Application
or	O
engine	O
that	O
interprets	O
JavaScript	B-Language
.	O
</s>
<s>
LOLCODE	B-Language
is	O
designed	O
to	O
resemble	O
the	O
speech	O
of	O
lolcats	O
.	O
</s>
<s>
While	O
the	O
semantics	B-Application
of	O
LOLCODE	B-Language
is	O
not	O
unusual	O
,	O
its	O
syntax	O
has	O
been	O
described	O
as	O
a	O
linguistic	O
phenomenon	O
,	O
representing	O
an	O
unusual	O
example	O
of	O
informal	O
speech	O
and	O
internet	O
slang	O
in	O
programming	O
.	O
</s>
<s>
Malbolge	B-Language
(	O
named	O
after	O
the	O
8th	O
circle	O
of	O
Hell	O
)	O
was	O
designed	O
to	O
be	O
the	O
most	O
difficult	O
and	O
esoteric	O
programming	O
language	O
.	O
</s>
<s>
Piet	B-Language
is	O
a	O
language	O
designed	O
by	O
David	O
Morgan-Mar	O
,	O
whose	O
programs	O
are	O
bitmaps	O
that	O
look	O
like	O
abstract	O
art	O
.	O
</s>
<s>
Variables	O
are	O
stored	O
in	O
memory	O
as	O
signed	O
integers	O
in	O
a	O
single	O
stack	B-Application
.	O
</s>
<s>
Most	O
specified	O
procedures	O
deal	O
with	O
operations	O
on	O
that	O
stack	B-Application
,	O
while	O
others	O
deal	O
with	O
input/output	O
and	O
with	O
the	O
rules	O
by	O
which	O
the	O
compilation	O
pointer	O
moves	O
.	O
</s>
<s>
Piet	B-Language
was	O
named	O
after	O
the	O
Dutch	O
painter	O
Piet	B-Language
Mondrian	B-Application
.	O
</s>
<s>
The	O
original	O
intended	O
name	O
,	O
Mondrian	B-Application
,	O
was	O
already	O
taken	O
by	O
an	B-Application
open-source	I-Application
statistical	I-Application
data-visualization	I-Application
system	I-Application
.	O
</s>
<s>
Shakespeare	B-Language
is	O
designed	O
to	O
make	O
programs	O
look	O
like	O
Shakespearean	O
plays	O
.	O
</s>
<s>
Unlambda	B-Language
is	O
a	O
minimalist	O
functional	B-Language
programming	I-Language
language	I-Language
based	O
on	O
SKI	B-Application
calculus	I-Application
,	O
but	O
combined	O
with	O
first-class	O
continuations	O
and	O
imperative	B-Application
I/O	O
(	O
with	O
input	O
usually	O
requiring	O
the	O
use	O
of	O
continuations	O
)	O
.	O
</s>
<s>
Whitespace	B-Language
uses	O
only	O
whitespace	B-Language
characters	O
(	O
space	O
,	O
tab	O
,	O
and	O
return	O
)	O
,	O
ignoring	O
all	O
other	O
characters	O
,	O
which	O
can	O
therefore	O
be	O
used	O
for	O
comments	O
.	O
</s>
<s>
This	O
is	O
the	O
reverse	O
of	O
many	O
traditional	O
languages	O
,	O
which	O
do	O
not	O
distinguish	O
between	O
different	O
whitespace	B-Language
characters	O
,	O
treating	O
tab	O
and	O
space	O
the	O
same	O
.	O
</s>
<s>
It	O
also	O
allows	O
Whitespace	B-Language
programs	O
to	O
be	O
hidden	O
in	O
the	O
source	O
code	O
of	O
programs	O
in	O
languages	O
like	O
C	B-Language
.	O
</s>
<s>
Daniel	O
Temkin	O
describes	O
Brainfuck	B-Language
as	O
"	O
refusing	O
to	O
ease	O
the	O
boundary	O
between	O
human	O
expression	O
and	O
assembly	B-Language
code	I-Language
and	O
thereby	O
taking	O
us	O
on	O
a	O
ludicrous	O
journey	O
of	O
logic	O
,	O
"	O
exposing	O
the	O
inherent	O
conflict	O
between	O
human	O
thinking	O
and	O
computer	O
logic	O
.	O
</s>
<s>
The	O
esolangs	O
wiki	O
community	O
derives	O
from	O
a	O
'	O
#esolangs	O
'	O
channel	O
on	O
various	O
IRC	B-Protocol
servers	O
,	O
which	O
influenced	O
the	O
creation	O
of	O
the	O
wiki	O
in	O
2005	O
.	O
</s>
