<s>
R	B-Language
packages	I-Language
are	O
extensions	B-Application
to	O
the	O
R	B-Language
statistical	I-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
R	B-Language
packages	I-Language
contain	O
code	O
,	O
data	O
,	O
and	O
documentation	O
in	O
a	O
standardised	O
collection	O
format	O
that	O
can	O
be	O
installed	O
by	O
users	O
of	O
R	B-Language
,	O
typically	O
via	O
a	O
centralised	O
software	B-Application
repository	I-Application
such	O
as	O
CRAN	O
(	O
the	O
Comprehensive	O
R	B-Language
Archive	O
Network	O
)	O
.	O
</s>
<s>
The	O
large	O
number	O
of	O
packages	O
available	O
for	O
R	B-Language
,	O
and	O
the	O
ease	O
of	O
installing	O
and	O
using	O
them	O
,	O
has	O
been	O
cited	O
as	O
a	O
major	O
factor	O
driving	O
the	O
widespread	O
adoption	O
of	O
the	O
language	O
in	O
data	O
science	O
.	O
</s>
<s>
Compared	O
to	O
libraries	B-Library
in	O
other	O
programming	O
language	O
,	O
R	B-Language
packages	I-Language
must	O
conform	O
to	O
a	O
relatively	O
strict	O
specification	O
.	O
</s>
<s>
The	O
Writing	O
R	B-Language
Extensions	B-Application
manual	O
specifies	O
a	O
standard	O
directory	B-Architecture
structure	I-Architecture
for	O
R	B-Language
source	O
code	O
,	O
data	O
,	O
documentation	O
,	O
and	O
package	O
metadata	O
,	O
which	O
enables	O
them	O
to	O
be	O
installed	O
and	O
loaded	O
using	O
R	B-Language
's	O
in-built	O
package	B-Application
management	I-Application
tools	O
.	O
</s>
<s>
According	O
to	O
John	O
Chambers	O
,	O
whilst	O
these	O
requirements	O
"	O
impose	O
considerable	O
demands	O
"	O
on	O
package	O
developers	O
,	O
they	O
improve	O
the	O
usability	B-General_Concept
and	O
long-term	O
stability	O
of	O
packages	O
for	O
end	O
users	O
.	O
</s>
<s>
The	O
Comprehensive	O
R	B-Language
Archive	O
Network	O
(	O
CRAN	O
)	O
is	O
R	B-Language
's	O
central	O
software	B-Application
repository	I-Application
,	O
supported	O
by	O
the	O
R	B-Language
Foundation	I-Language
.	O
</s>
<s>
It	O
contains	O
an	O
archive	O
of	O
the	O
latest	O
and	O
previous	O
versions	O
of	O
the	O
R	B-Language
distribution	O
,	O
documentation	O
,	O
and	O
contributed	O
R	B-Language
packages	I-Language
.	O
</s>
<s>
It	O
includes	O
both	O
source	O
packages	O
and	O
pre-compiled	O
binaries	B-Application
for	O
Windows	O
and	O
macOS	B-Application
.	O
</s>
<s>
CRAN	O
was	O
created	O
by	O
Kurt	O
Hornik	O
and	O
Friedrich	O
Leisch	O
in	O
1997	O
,	O
with	O
the	O
name	O
paralleling	O
other	O
early	O
packing	O
systems	O
such	O
as	O
TeX	B-Application
's	O
CTAN	B-General_Concept
(	O
released	O
1992	O
)	O
and	O
Perl	B-Language
's	O
CPAN	B-Language
(	O
released	O
1995	O
)	O
.	O
</s>
<s>
The	O
"	O
Task	O
Views	O
"	O
page	O
(	O
subject	O
list	O
)	O
on	O
the	O
CRAN	O
website	O
lists	O
a	O
wide	O
range	O
of	O
tasks	O
(	O
in	O
fields	O
such	O
as	O
finance	O
,	O
genetics	O
,	O
high	O
performance	O
computing	O
,	O
machine	O
learning	O
,	O
medical	O
imaging	O
,	O
meta-analysis	O
,	O
social	O
sciences	O
and	O
spatial	O
statistics	O
)	O
for	O
which	O
R	B-Language
packages	I-Language
are	O
available	O
.	O
</s>
<s>
Since	O
each	O
submission	O
is	O
manually	O
reviewed	O
by	O
a	O
small	O
team	O
of	O
CRAN	O
maintainers	O
,	O
many	O
of	O
whom	O
,	O
according	O
to	O
R	B-Language
core	O
developer	O
Peter	O
Dalgaard	O
,	O
are	O
"	O
approaching	O
pensionable	O
age	O
"	O
,	O
there	O
is	O
a	O
concern	O
that	O
this	O
system	O
is	O
not	O
sustainable	O
in	O
the	O
long	O
term	O
.	O
</s>
<s>
The	O
growth	O
of	O
CRAN	O
has	O
exposed	O
limitations	O
of	O
its	O
dependency	B-Application
management	I-Application
infrastructure	O
,	O
particularly	O
the	O
fact	O
that	O
it	O
assumes	O
that	O
dependencies	B-Application
always	O
refer	O
to	O
the	O
latest	O
version	O
of	O
a	O
package	O
,	O
meaning	O
that	O
new	O
releases	O
of	O
CRAN	O
packages	O
must	O
always	O
be	O
backwards	B-General_Concept
compatible	I-General_Concept
,	O
and	O
that	O
CRAN	O
packages	O
cannot	O
have	O
dependencies	B-Application
that	O
are	O
not	O
on	O
CRAN	O
.	O
</s>
<s>
The	O
Microsoft	O
R	B-Language
Application	O
Network	O
(	O
MRAN	O
)	O
is	O
a	O
mirror	O
of	O
CRAN	O
maintained	O
by	O
Microsoft	O
which	O
is	O
based	O
on	O
the	O
company	O
's	O
downstream	O
distribution	O
of	O
R	B-Language
,	O
Microsoft	O
R	B-Language
Open	O
(	O
formerly	O
Revolution	O
R	B-Language
Open	O
)	O
.	O
</s>
<s>
It	O
also	O
includes	O
an	O
archive	O
of	O
daily	O
CRAN	O
snapshots	O
,	O
branded	O
as	O
the	O
"	O
CRAN	O
Time	O
Machine	O
"	O
,	O
which	O
enables	O
users	O
of	O
MRAN	O
to	O
bypass	O
the	O
dependency	B-Application
versioning	O
limitations	O
of	O
CRAN	O
by	O
installing	O
a	O
fixed	O
set	O
of	O
R	B-Language
package	I-Language
versions	O
via	O
the	O
package	O
checkpoint	O
.	O
</s>
<s>
RStudio	B-Application
Package	B-Application
Manager	I-Application
is	O
a	O
similar	O
tool	O
produced	O
by	O
RStudio	B-Application
,	O
which	O
in	O
addition	O
to	O
CRAN	O
snapshots	O
includes	O
an	O
archive	O
of	O
R	B-Language
packages	I-Language
from	O
Bioconductor	B-Application
and	O
Python	B-Language
packages	I-Language
from	O
the	O
Python	B-Language
Package	I-Language
Index	I-Language
.	O
</s>
<s>
It	O
also	O
distributes	O
pre-compiled	O
binary	O
packages	O
for	O
Linux	O
(	O
only	O
Windows	O
and	O
macOS	B-Application
binaries	B-Application
are	O
included	O
on	O
CRAN	O
)	O
.	O
</s>
<s>
The	O
Bioconductor	B-Application
project	O
provides	O
R	B-Language
packages	I-Language
for	O
the	O
analysis	O
of	O
genomic	O
data	O
.	O
</s>
<s>
R-Forge	O
,	O
is	O
a	O
central	O
platform	O
for	O
the	O
collaborative	O
development	O
of	O
R	B-Language
packages	I-Language
,	O
R-related	O
software	O
,	O
and	O
projects	O
.	O
</s>
<s>
R-Forge	O
also	O
hosts	O
many	O
unpublished	O
beta	O
packages	O
,	O
and	O
development	O
versions	O
of	O
CRAN	O
packages	O
.	O
</s>
<s>
R	B-Language
is	O
distributed	O
with	O
fifteen	O
"	O
base	O
packages	O
"	O
:	O
base	O
,	O
compiler	B-Language
,	O
datasets	O
,	O
grDevices	O
,	O
graphics	O
,	O
grid	O
,	O
methods	O
,	O
parallel	O
,	O
splines	O
,	O
stats	O
,	O
stats4	O
,	O
tcltk	O
,	O
tools	O
,	O
translations	O
,	O
and	O
utils	O
.	O
</s>
<s>
In	O
addition	O
,	O
there	O
are	O
fifteen	O
"	O
recommended	O
packages	O
"	O
from	O
CRAN	O
which	O
are	O
included	O
with	O
binary	O
distributions	O
of	O
R	B-Language
:	O
KernSmooth	O
,	O
MASS	O
,	O
Matrix	O
,	O
boot	O
,	O
class	O
,	O
cluster	O
,	O
codetools	O
,	O
foreign	O
,	O
lattice	O
,	O
mgcv	O
,	O
nlme	O
,	O
nnet	O
,	O
rpart	O
,	O
spatial	O
,	O
and	O
survival	O
.	O
</s>
<s>
A	O
group	O
of	O
packages	O
called	O
the	O
Tidyverse	B-Algorithm
,	O
which	O
can	O
be	O
considered	O
a	O
"	O
dialect	O
of	O
the	O
R	B-Language
language	I-Language
"	O
,	O
is	O
increasingly	O
popular	O
in	O
the	O
R	B-Language
ecosystem	O
.	O
</s>
<s>
As	O
of	O
2020-06-13	O
,	O
Metacran	O
listed	O
7	O
of	O
the	O
8	O
core	O
packages	O
of	O
the	O
Tidyverse	B-Algorithm
in	O
the	O
list	O
of	O
most	O
download	O
R	B-Language
packages	I-Language
.	O
</s>
<s>
The	O
group	O
of	O
packages	O
strives	O
to	O
provide	O
a	O
cohesive	O
collection	O
of	O
functions	O
to	O
deal	O
with	O
common	O
data	O
science	O
tasks	O
,	O
including	O
data	O
import	O
,	O
cleaning	O
,	O
transformation	O
and	O
visualisation	O
(	O
notably	O
with	O
the	O
ggplot2	B-Application
package	O
)	O
.	O
</s>
<s>
The	O
R	B-Language
Infrastructure	O
packages	O
support	O
coding	O
and	O
the	O
development	O
of	O
R	B-Language
packages	I-Language
and	O
as	O
of	O
2021-05-04	O
,	O
Metacran	O
lists	O
16	O
of	O
these	O
packages	O
among	O
the	O
25	O
most	O
downloaded	O
packages	O
.	O
</s>
