<s>
Logo	O
is	O
an	O
educational	B-Language
programming	I-Language
language	I-Language
,	O
designed	O
in	O
1967	O
by	O
Wally	O
Feurzeig	O
,	O
Seymour	O
Papert	O
,	O
and	O
Cynthia	O
Solomon	O
.	O
</s>
<s>
A	O
general-purpose	O
language	O
,	O
Logo	O
is	O
widely	O
known	O
for	O
its	O
use	O
of	O
turtle	B-Application
graphics	I-Application
,	O
in	O
which	O
commands	O
for	O
movement	O
and	O
drawing	O
produced	O
line	O
or	O
vector	O
graphics	O
,	O
either	O
on	O
screen	O
or	O
with	O
a	O
small	O
robot	O
termed	O
a	O
turtle	O
.	O
</s>
<s>
The	O
language	O
was	O
conceived	O
to	O
teach	O
concepts	O
of	O
programming	O
related	O
to	O
Lisp	B-Language
and	O
only	O
later	O
to	O
enable	O
what	O
Papert	O
called	O
"	O
body-syntonic	O
reasoning	O
"	O
,	O
where	O
students	O
could	O
understand	O
,	O
predict	O
,	O
and	O
reason	O
about	O
the	O
turtle	O
's	O
motion	O
by	O
imagining	O
what	O
they	O
would	O
do	O
if	O
they	O
were	O
the	O
turtle	O
.	O
</s>
<s>
There	O
are	O
substantial	O
differences	O
among	O
the	O
many	O
dialects	O
of	O
Logo	O
,	O
and	O
the	O
situation	O
is	O
confused	O
by	O
the	O
regular	O
appearance	O
of	O
turtle	B-Application
graphics	I-Application
programs	O
that	O
are	O
named	O
Logo	O
.	O
</s>
<s>
Logo	O
is	O
a	O
multi-paradigm	O
adaptation	O
and	O
dialect	O
of	O
Lisp	B-Language
,	O
a	O
functional	B-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
There	O
is	O
no	O
standard	O
Logo	O
,	O
but	O
UCBLogo	B-Application
has	O
the	O
best	O
facilities	O
for	O
handling	O
lists	O
,	O
files	O
,	O
I/O	O
,	O
and	O
recursion	O
in	O
scripts	O
,	O
and	O
can	O
be	O
used	O
to	O
teach	O
all	O
computer	O
science	O
concepts	O
,	O
as	O
UC	O
Berkeley	O
lecturer	O
Brian	O
Harvey	O
did	O
in	O
his	O
Computer	O
Science	O
Logo	O
Style	O
trilogy	O
.	O
</s>
<s>
Logo	O
is	O
usually	O
an	O
interpreted	B-Application
language	I-Application
,	O
although	O
compiled	O
Logo	O
dialects	O
(	O
such	O
as	O
Lhogho	O
and	O
Liogo	O
)	O
have	O
been	O
developed	O
.	O
</s>
<s>
Its	O
intellectual	O
roots	O
are	O
in	O
artificial	B-Application
intelligence	I-Application
,	O
mathematical	O
logic	O
and	O
developmental	O
psychology	O
.	O
</s>
<s>
The	O
first	O
implementation	O
of	O
Logo	O
,	O
called	O
Ghost	O
,	O
was	O
written	O
in	O
LISP	B-Language
on	O
a	O
PDP-1	B-Device
.	O
</s>
<s>
Modeled	O
on	O
LISP	B-Language
,	O
the	O
design	O
goals	O
of	O
Logo	O
included	O
accessible	O
power	O
and	O
informative	O
error	O
messages	O
.	O
</s>
<s>
Turtle	B-Application
graphics	I-Application
were	O
added	O
to	O
the	O
Logo	O
language	O
by	O
Seymour	O
Papert	O
in	O
the	O
late	O
1960s	O
to	O
support	O
Papert	O
's	O
version	O
of	O
the	O
turtle	O
robot	O
,	O
a	O
simple	O
robot	O
controlled	O
from	O
the	O
user	O
's	O
workstation	O
that	O
is	O
designed	O
to	O
carry	O
out	O
the	O
drawing	O
functions	O
assigned	O
to	O
it	O
using	O
a	O
small	O
retractable	O
pen	O
set	O
into	O
or	O
attached	O
to	O
the	O
robot	O
's	O
body	O
.	O
</s>
<s>
For	O
instance	O
,	O
the	O
idea	O
of	O
turtle	B-Application
graphics	I-Application
is	O
also	O
useful	O
in	O
Lindenmayer	B-Language
system	I-Language
for	O
generating	O
fractals	B-Application
.	O
</s>
<s>
There	O
are	O
two	O
popular	O
implementations	O
:	O
Massachusetts	O
Institute	O
of	O
Technology	O
's	O
StarLogo	B-Language
and	O
Northwestern	O
University	O
Center	O
for	O
Connected	O
Learning	O
's	O
(	O
CCL	O
)	O
NetLogo	B-Language
.	O
</s>
<s>
NetLogo	B-Language
is	O
widely	O
used	O
in	O
agent-based	O
simulation	O
in	O
the	O
biological	O
and	O
social	O
sciences	O
.	O
</s>
<s>
Commercial	O
implementations	O
widely	O
used	O
in	O
schools	O
include	O
MicroWorlds	B-Language
Logo	O
and	O
Imagine	O
Logo	O
.	O
</s>
<s>
Apple	O
Logo	O
for	O
the	O
Apple	B-Device
II	I-Device
Plus	O
and	O
Apple	O
Logo	O
Writer	O
for	O
the	O
Apple	B-Device
IIe	I-Device
,	O
developed	O
by	O
Logo	O
Computer	O
Systems	O
,	O
Inc	O
.	O
(	O
LCSI	B-Language
)	O
,	O
were	O
the	O
most	O
broadly	O
used	O
and	O
prevalent	O
early	O
implementations	O
of	O
Logo	O
that	O
peaked	O
in	O
the	O
early	O
to	O
mid-1980s	O
.	O
</s>
<s>
Aquarius	B-Device
LOGO	O
was	O
released	O
in	O
1982	O
on	O
cartridge	O
by	O
Mattel	O
for	O
the	O
Aquarius	B-Device
home	O
computer	O
.	O
</s>
<s>
Atari	B-Application
Logo	I-Application
was	O
released	O
on	O
cartridge	O
by	O
Atari	O
for	O
the	O
Atari	B-Device
8-bit	I-Device
family	I-Device
.	O
</s>
<s>
Color	O
Logo	O
was	O
released	O
in	O
1983	O
on	O
cartridge	O
(	O
26-2722	O
)	O
and	O
disk	O
(	O
26-2721	O
)	O
by	O
Tandy	O
for	O
the	O
TRS-80	B-Device
Color	I-Device
Computer	I-Device
.	O
</s>
<s>
The	O
Commodore	O
64	O
version	O
(	O
C64105	O
)	O
was	O
released	O
on	O
diskette	O
in	O
1983	O
;	O
the	O
Plus/4	B-Operating_System
version	O
(	O
T263001	O
)	O
was	O
released	O
on	O
cartridge	O
in	O
1984	O
.	O
</s>
<s>
ExperLogo	O
was	O
released	O
in	O
1985	O
on	O
floppy	O
by	O
Expertelligence	O
Inc	O
.	O
for	O
the	O
Macintosh	B-Device
128K	I-Device
.	O
</s>
<s>
Hot-Logo	O
was	O
released	O
in	O
the	O
mid-1980s	O
by	O
EPCOM	O
for	O
the	O
MSX	B-Operating_System
8-bit	O
computers	O
with	O
its	O
own	O
set	O
of	O
commands	O
in	O
Brazilian	O
Portuguese	O
.	O
</s>
<s>
TI	O
Logo	O
(	O
for	O
the	O
TI	B-Device
99/4A	I-Device
computer	O
)	O
was	O
used	O
in	O
primary	O
schools	O
,	O
emphasizing	O
Logo	O
's	O
usefulness	O
in	O
teaching	O
computing	O
fundamentals	O
to	O
novice	O
programmers	O
.	O
</s>
<s>
It	O
ran	O
on	O
Apple	B-Device
II	I-Device
computers	O
,	O
with	O
the	O
aid	O
of	O
a	O
Sprite	O
Card	O
inserted	O
in	O
one	O
of	O
the	O
computer	O
's	O
slots	O
.	O
</s>
<s>
IBM	O
marketed	O
their	O
own	O
version	O
of	O
Logo	O
(	O
P/N	O
6024076	O
)	O
,	O
developed	O
jointly	O
by	O
Logo	O
Computer	O
Systems	O
,	O
Inc	O
.	O
(	O
LCSI	B-Language
)	O
,	O
for	O
their	O
then-new	O
IBM	B-Device
PC	I-Device
.	O
</s>
<s>
ObjectLOGO	B-Language
is	O
a	O
variant	O
of	O
Logo	O
with	O
object-oriented	B-Language
programming	I-Language
extensions	O
and	O
lexical	O
scoping	O
.	O
</s>
<s>
Logo	O
was	O
developed	O
by	O
Digital	O
Research	O
and	O
distributed	O
in	O
computers	O
including	O
the	O
IBM	B-Device
PCjr	I-Device
,	O
Atari	O
ST	O
and	O
the	O
Amstrad	B-Device
CPC	I-Device
.	O
</s>
<s>
It	O
is	O
a	O
commercial	O
implementation	O
of	O
Logo	O
for	O
the	O
8-bit	O
BBC	B-Device
Micro	I-Device
and	O
Acorn	B-Device
Electron	I-Device
computers	O
.	O
</s>
<s>
In	O
February	O
1990	O
,	O
Electron	O
User	O
published	O
Timothy	O
Grantham	O
's	O
simple	O
implementation	O
of	O
Logo	O
for	O
the	O
Acorn	B-Device
Electron	I-Device
under	O
the	O
article	O
"	O
Talking	O
Turtle	O
"	O
.	O
</s>
<s>
Lego	B-Language
Logo	O
is	O
a	O
version	O
of	O
Logo	O
that	O
can	O
manipulate	O
robotic	O
Lego	B-Language
bricks	O
attached	O
to	O
a	O
computer	O
.	O
</s>
<s>
It	O
was	O
implemented	O
on	O
the	O
Apple	B-Device
II	I-Device
computing	O
platform	O
and	O
was	O
used	O
in	O
American	O
and	O
other	O
grade	O
schools	O
in	O
the	O
late	O
1980s	O
and	O
early	O
1990s	O
.	O
</s>
<s>
Lego	B-Language
Logo	O
is	O
a	O
precursor	O
to	O
Scratch	B-Language
.	O
</s>
<s>
UCBLogo	B-Application
,	O
also	O
known	O
as	O
Berkeley	O
Logo	O
,	O
is	O
a	O
free	O
,	O
cross-platform	O
implementation	O
of	O
standard	O
Logo	O
last	O
released	O
in	O
2009	O
.	O
</s>
<s>
George	O
Mills	O
at	O
MIT	O
used	O
UCBLogo	B-Application
as	O
the	O
basis	O
for	O
MSWLogo	B-Application
which	O
is	O
more	O
refined	O
and	O
also	O
free	O
.	O
</s>
<s>
Jim	O
Muller	O
wrote	O
a	O
book	O
,	O
The	O
Great	O
Logo	O
Adventure	O
,	O
which	O
was	O
a	O
complete	O
Logo	O
manual	O
and	O
which	O
used	O
MSWLogo	B-Application
as	O
the	O
demonstration	O
language	O
.	O
</s>
<s>
MSWLogo	B-Application
has	O
evolved	O
into	O
FMSLogo	B-Application
.	O
</s>
<s>
aUCBLogo	O
is	O
a	O
rewrite	O
and	O
enhancement	O
of	O
UCBLogo	B-Application
.	O
</s>
<s>
LibreLogo	B-Application
is	O
an	O
extension	O
to	O
some	O
versions	O
of	O
LibreOffice	O
.	O
</s>
<s>
Released	O
in	O
2012	O
,	O
it	O
is	O
written	O
in	O
Python	B-Language
.	O
</s>
<s>
POOL	O
is	O
a	O
dialect	O
of	O
Logo	O
with	O
object-oriented	B-Language
extensions	O
,	O
implemented	O
in	O
2014	O
.	O
</s>
<s>
POOL	O
programs	O
are	O
compiled	O
and	O
run	O
in	O
the	O
graphical	O
IDE	O
on	O
Microsoft	B-Application
Windows	I-Application
.	O
</s>
<s>
A	O
simplified	O
,	O
cross-platform	O
environment	O
is	O
available	O
for	O
systems	O
supporting	O
.NET	B-Application
Framework	I-Application
.	O
</s>
<s>
QLogo	O
is	O
an	O
open-source	O
and	O
cross-platform	O
rewrite	O
of	O
UCBLogo	B-Application
with	O
nearly	O
full	O
UCB	O
compatibility	O
that	O
uses	O
hardware-accelerated	O
graphics	O
.	O
</s>
<s>
Lynx	O
is	O
an	O
online	O
version	O
of	O
Logo	O
developed	O
by	O
Logo	B-Language
Computer	I-Language
Systems	I-Language
Inc	I-Language
.	I-Language
</s>
<s>
LogoMor	O
is	O
an	O
open-source	O
online	O
3D	O
Logo	O
interpreter	B-Application
based	O
on	O
JavaScript	O
and	O
p5.js	O
.	O
</s>
<s>
LbyM	O
is	O
an	O
open-source	O
online	O
Logo	O
interpreter	B-Application
based	O
on	O
JavaScript	O
,	O
created	O
and	O
actively	O
developed	O
(	O
as	O
of	O
2021	O
)	O
for	O
Sonoma	O
State	O
University	O
's	O
Learning	O
by	O
Making	O
program	O
.	O
</s>
<s>
Logo	O
was	O
a	O
primary	O
influence	O
on	O
the	O
Smalltalk	B-Application
programming	I-Application
language	I-Application
.	O
</s>
<s>
It	O
is	O
also	O
the	O
main	O
influence	O
on	O
the	O
Etoys	B-Application
educational	B-Language
programming	O
environment	O
and	O
language	O
,	O
which	O
is	O
essentially	O
a	O
Logo	O
variant	O
written	O
in	O
Squeak	B-Operating_System
(	O
itself	O
a	O
variant	O
of	O
Smalltalk	B-Application
)	O
.	O
</s>
<s>
Logo	O
influenced	O
the	O
procedure/method	O
model	O
in	O
AgentSheets	B-Language
and	O
AgentCubes	B-Language
to	O
program	O
agents	O
similar	O
to	O
the	O
notion	O
of	O
a	O
turtle	O
in	O
Logo	O
.	O
</s>
<s>
KTurtle	O
is	O
a	O
variation	O
of	O
Logo	O
implemented	O
at	O
Qt	B-Language
for	O
the	O
KDE	B-Application
environment	O
loosely	O
based	O
on	O
Logo	O
.	O
</s>
<s>
Two	O
more	O
results	O
of	O
Logo	O
's	O
influence	O
are	O
Kojo	B-Language
,	O
a	O
variant	O
of	O
Scala	O
,	O
and	O
Scratch	B-Language
,	O
a	O
visual	O
,	O
drag-and-drop	O
language	O
which	O
runs	O
in	O
a	O
web	O
browser	O
.	O
</s>
