<s>
Keras	B-Algorithm
is	O
an	O
open-source	B-Application
software	I-Application
library	O
that	O
provides	O
a	O
Python	B-Language
interface	O
for	O
artificial	B-Architecture
neural	I-Architecture
networks	I-Architecture
.	O
</s>
<s>
Keras	B-Algorithm
acts	O
as	O
an	O
interface	O
for	O
the	O
TensorFlow	B-Language
library	O
.	O
</s>
<s>
Up	O
until	O
version	O
2.3	O
,	O
Keras	B-Algorithm
supported	O
multiple	O
backends	O
,	O
including	O
TensorFlow	B-Language
,	O
Microsoft	B-Algorithm
Cognitive	I-Algorithm
Toolkit	I-Algorithm
,	O
Theano	B-Algorithm
,	O
and	O
PlaidML	B-Application
.	O
</s>
<s>
As	O
of	O
version	O
2.4	O
,	O
only	O
TensorFlow	B-Language
is	O
supported	O
.	O
</s>
<s>
Designed	O
to	O
enable	O
fast	O
experimentation	O
with	O
deep	B-Algorithm
neural	I-Algorithm
networks	I-Algorithm
,	O
it	O
focuses	O
on	O
being	O
user-friendly	O
,	O
modular	O
,	O
and	O
extensible	O
.	O
</s>
<s>
It	O
was	O
developed	O
as	O
part	O
of	O
the	O
research	O
effort	O
of	O
project	O
ONEIROS	O
(	O
Open-ended	O
Neuro-Electronic	O
Intelligent	O
Robot	O
Operating	O
System	O
)	O
,	O
and	O
its	O
primary	O
author	O
and	O
maintainer	O
is	O
François	O
Chollet	O
,	O
a	O
Google	B-Application
engineer	O
.	O
</s>
<s>
Chollet	O
is	O
also	O
the	O
author	O
of	O
the	O
Xception	O
deep	O
neural	B-Architecture
network	I-Architecture
model	I-Architecture
.	O
</s>
<s>
Keras	B-Algorithm
contains	O
numerous	O
implementations	O
of	O
commonly	O
used	O
neural-network	O
building	O
blocks	O
such	O
as	O
layers	O
,	O
objectives	O
,	O
activation	B-Algorithm
functions	I-Algorithm
,	O
optimizers	O
,	O
and	O
a	O
host	O
of	O
tools	O
to	O
make	O
working	O
with	O
image	O
and	O
text	O
data	O
easier	O
to	O
simplify	O
the	O
coding	O
necessary	O
for	O
writing	O
deep	O
neural	B-Architecture
network	I-Architecture
code	O
.	O
</s>
<s>
The	O
code	O
is	O
hosted	O
on	O
GitHub	B-Application
,	O
and	O
community	O
support	O
forums	O
include	O
the	O
GitHub	B-Application
issues	O
page	O
,	O
and	O
a	O
Slack	B-Protocol
channel	O
.	O
</s>
<s>
In	O
addition	O
to	O
standard	O
neural	B-Architecture
networks	I-Architecture
,	O
Keras	B-Algorithm
has	O
support	O
for	O
convolutional	B-Architecture
and	O
recurrent	B-Algorithm
neural	I-Algorithm
networks	I-Algorithm
.	O
</s>
<s>
It	O
supports	O
other	O
common	O
utility	O
layers	O
like	O
dropout	B-Algorithm
,	O
batch	B-General_Concept
normalization	I-General_Concept
,	O
and	O
pooling	O
.	O
</s>
<s>
Keras	B-Algorithm
allows	O
users	O
to	O
productize	O
deep	O
models	O
on	O
smartphones	O
(	O
iOS	B-Application
and	O
Android	B-Application
)	O
,	O
on	O
the	O
web	O
,	O
or	O
on	O
the	O
Java	B-Language
Virtual	I-Language
Machine	I-Language
.	O
</s>
<s>
It	O
also	O
allows	O
use	O
of	O
distributed	O
training	O
of	O
deep-learning	B-Algorithm
models	O
on	O
clusters	O
of	O
Graphics	B-Architecture
processing	I-Architecture
units	I-Architecture
(	O
GPU	B-Architecture
)	O
and	O
tensor	B-Device
processing	I-Device
units	I-Device
(	O
TPU	O
)	O
.	O
</s>
