<s>
TYPO3	O
is	O
a	O
free	B-Application
and	O
open-source	B-Application
Web	O
content	B-Protocol
management	I-Protocol
system	I-Protocol
written	O
in	O
PHP	B-Application
.	O
</s>
<s>
It	O
is	O
released	O
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
.	O
</s>
<s>
It	O
can	O
run	O
on	O
a	O
variety	O
of	O
web	B-Application
servers	I-Application
,	O
such	O
as	O
Apache	B-Application
,	O
Nginx	B-Operating_System
or	O
IIS	B-Application
,	O
and	O
on	O
top	O
of	O
many	O
operating	O
systems	O
,	O
including	O
Linux	B-Application
,	O
Microsoft	B-Application
Windows	I-Application
,	O
FreeBSD	B-Operating_System
,	O
macOS	B-Application
and	O
OS/2	B-Application
.	O
</s>
<s>
TYPO3	O
is	O
similar	O
to	O
other	O
popular	O
content	B-Protocol
management	I-Protocol
systems	I-Protocol
such	O
as	O
,	O
Drupal	B-Application
,	O
Joomla	B-Protocol
!	I-Protocol
</s>
<s>
and	O
WordPress	B-Application
.	O
</s>
<s>
TYPO3	O
supports	O
publishing	O
content	O
in	O
multiple	O
languages	O
due	O
to	O
its	O
built-in	O
localization	B-General_Concept
system	O
.	O
</s>
<s>
Due	O
to	O
its	O
features	O
like	O
editorial	O
workplace	O
and	O
workflow	O
,	O
advanced	O
frontend	O
editing	O
,	O
scalability	O
and	O
maturity	O
,	O
TYPO3	O
classifies	O
itself	O
as	O
an	O
enterprise	O
level	O
content	B-Protocol
management	I-Protocol
system	I-Protocol
.	O
</s>
<s>
More	O
than	O
5000	O
extensions	O
are	O
currently	O
available	O
for	O
TYPO3	O
for	O
download	O
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
from	O
a	O
repository	O
called	O
the	O
TYPO3	O
Extension	O
Repository	O
,	O
or	O
TER	O
.	O
</s>
<s>
TYPO3	O
can	O
run	O
on	O
most	O
HTTP	B-Application
servers	I-Application
such	O
as	O
Apache	B-Application
,	O
Nginx	B-Operating_System
or	O
IIS	B-Application
on	O
top	O
of	O
Linux	B-Application
,	O
Microsoft	B-Application
Windows	I-Application
or	O
macOS	B-Application
.	O
</s>
<s>
It	O
uses	O
PHP	B-Application
7.2	O
or	O
newer	O
and	O
any	O
relational	O
database	O
supported	O
by	O
the	O
TYPO3	O
DBAL	B-Application
including	O
MySQL	B-Application
,	O
MariaDB	B-Application
,	O
PostgreSQL	B-Application
,	O
and	O
SQLite	B-Language
.	O
</s>
<s>
Some	O
3rd-party	O
extensions	O
not	O
using	O
the	O
database	O
API	O
support	O
MySQL	B-Application
as	O
the	O
only	O
database	O
engine	O
.	O
</s>
<s>
The	O
system	O
can	O
be	O
run	O
on	O
any	O
web	B-Application
server	I-Application
with	O
at	O
least	O
256	O
MB	O
RAM	B-Architecture
and	O
a	O
CPU	B-General_Concept
appropriate	O
for	O
that	O
RAM	B-Architecture
.	O
</s>
<s>
The	O
backend	O
can	O
be	O
displayed	O
in	O
any	O
modern	O
browser	O
with	O
JavaScript	B-Language
.	O
</s>
<s>
Like	O
most	O
modern	O
CMSes	B-Protocol
,	O
TYPO3	O
follows	O
the	O
policy	O
of	O
separation	O
of	O
content	O
and	O
layout	O
:	O
The	O
website	O
content	O
is	O
stored	O
in	O
a	O
relational	O
database	O
,	O
while	O
the	O
page	O
templates	O
are	O
stored	O
on	O
the	O
file	O
system	O
.	O
</s>
<s>
Internally	O
,	O
TYPO3	O
is	O
managed	O
by	O
various	O
PHP	B-Application
arrays	O
.	O
</s>
<s>
It	O
can	O
be	O
extended	O
by	O
custom	O
view	O
helpers	O
written	O
in	O
PHP	B-Application
.	O
</s>
<s>
In	O
Typoscript	O
,	O
configuration	O
values	O
are	O
defined	O
,	O
which	O
are	O
parsed	O
into	O
a	O
system-wide	O
PHP	B-Application
array	O
.	O
</s>
<s>
As	O
TYPO3	B-Language
CMS	I-Language
is	O
written	O
in	O
PHP	B-Application
,	O
therefore	O
most	O
features	O
can	O
be	O
modified	O
or	O
extended	O
by	O
experienced	O
users	O
.	O
</s>
<s>
Generally	O
,	O
extensions	O
are	O
written	O
in	O
PHP	B-Application
.	O
</s>
<s>
The	O
full	O
command	O
set	O
of	O
PHP	B-Application
5.3	O
can	O
be	O
used	O
(	O
regarded	O
the	O
system	O
requirements	O
of	O
the	O
specific	O
TYPO3	O
version	O
)	O
,	O
but	O
TYPO3	O
also	O
provides	O
several	O
library	O
classes	O
for	O
better	O
efficiency	O
:	O
Best	O
known	O
and	O
most	O
used	O
is	O
the	O
piBase	O
library	O
class	O
.	O
</s>
<s>
Extbase	O
itself	O
is	O
a	O
backport	O
of	O
some	O
features	O
of	O
FLOW3	B-Language
,	O
a	O
general	O
web	O
application	O
framework	O
.	O
</s>
<s>
Published	O
as	O
FLOW3	B-Language
,	O
it	O
along	O
with	O
various	O
other	O
packages	O
then	O
served	O
as	O
the	O
basis	O
for	O
the	O
start	O
of	O
development	O
of	O
project	O
Phoenix	O
.	O
</s>
<s>
In	O
May	O
2015	O
the	O
TYPO3	O
Association	O
and	O
the	O
Neos	O
team	O
decided	O
to	O
go	O
separate	O
ways	O
,	O
with	O
TYPO3	B-Language
CMS	I-Language
remaining	O
the	O
only	O
CMS	O
product	O
endorsed	O
by	O
the	O
Association	O
and	O
the	O
Neos	O
team	O
publishing	O
Neos	O
as	O
a	O
stand-alone	O
CMS	O
without	O
any	O
connection	O
to	O
the	O
TYPO3	O
world	O
.	O
</s>
