<s>
Web	B-Language
Dynpro	I-Language
(	O
WD	O
)	O
is	O
a	O
web	O
application	O
technology	O
developed	O
by	O
SAP	B-Application
SE	I-Application
that	O
focuses	O
on	O
the	O
development	O
of	O
server-side	O
business	O
applications	O
.	O
</s>
<s>
For	O
modern	O
releases	O
(	O
for	O
instance	O
as	O
of	O
NetWeaver	B-Application
750	O
,	O
software	O
layer	O
SAP_UI	O
)	O
the	O
user	B-Application
interface	I-Application
is	O
rendered	O
according	O
to	O
the	O
HTML5	B-Application
web	O
standard	O
.	O
</s>
<s>
Since	O
Netweaver	B-Application
754	O
(	O
software	O
layer	O
SAP_UI	O
,	O
ABAP	B-Language
Platform	O
1909	O
)	O
a	O
touch	B-Application
enabled	O
user	B-Application
interface	I-Application
is	O
available	O
.	O
</s>
<s>
The	O
newly	O
released	O
versions	O
usually	O
follow	O
the	O
SAP	B-Application
Fiori	O
design	O
principles	O
.	O
</s>
<s>
One	O
of	O
its	O
main	O
design	O
features	O
is	O
that	O
the	O
user	B-Application
interface	I-Application
is	O
defined	O
in	O
an	O
entirely	O
declarative	O
manner	O
.	O
</s>
<s>
Web	B-Language
Dynpro	I-Language
applications	O
can	O
be	O
developed	O
using	O
either	O
the	O
Java	B-Language
(	O
Web	B-Language
Dynpro	I-Language
for	O
Java	B-Language
,	O
WDJ	O
or	O
WD4J	O
)	O
or	O
ABAP	B-Language
(	O
Web	B-Language
Dynpro	I-Language
ABAP	I-Language
,	O
WDA	O
or	O
WD4A	O
)	O
development	O
infrastructure	O
.	O
</s>
<s>
The	O
earliest	O
version	O
of	O
Web	B-Language
Dynpro	I-Language
appeared	O
in	O
2003	O
and	O
was	O
based	O
on	O
Java	B-Language
.	O
</s>
<s>
This	O
variant	O
was	O
released	O
approximately	O
18	O
months	O
before	O
the	O
ABAP	B-Language
variant	O
.	O
</s>
<s>
As	O
of	O
2010	O
,	O
the	O
Java	B-Language
variant	O
of	O
Web	B-Language
Dynpro	I-Language
was	O
put	O
into	O
maintenance	O
mode	O
.	O
</s>
<s>
WD	O
follows	O
a	O
design	O
architecture	O
based	O
on	O
an	O
interpretation	O
of	O
the	O
MVC	O
design	O
pattern	O
and	O
uses	O
a	O
model	B-Language
driven	I-Language
development	I-Language
approach	O
(	O
"	O
minimize	O
coding	O
,	O
maximize	O
design	O
"	O
)	O
.	O
</s>
<s>
The	O
Web	B-Language
Dynpro	I-Language
Framework	O
is	O
a	O
server-side	O
runtime	O
environment	O
into	O
which	O
many	O
dedicated	O
"	O
hook	O
methods	O
"	O
are	O
available	O
.	O
</s>
<s>
Web	B-Language
Dynpro	I-Language
is	O
aimed	O
at	O
the	O
development	O
of	O
business	O
applications	O
that	O
follow	O
standardized	O
UI	O
principles	O
,	O
applications	O
that	O
connect	O
to	O
backend	O
systems	O
and	O
which	O
are	O
scalable	O
.	O
</s>
<s>
Declarative	O
way	O
of	O
development	O
:	O
Web	B-Language
Dynpro	I-Language
offers	O
a	O
graphical	O
and	O
declarative	O
means	O
of	O
UI	O
development	O
.	O
</s>
<s>
Separation	O
of	O
user	B-Application
interface	I-Application
and	O
business	O
logic	O
:	O
One	O
advantage	O
of	O
Web	B-Language
Dynpro	I-Language
over	O
SAP	B-Application
GUI	O
is	O
the	O
separation	O
between	O
business	O
logic	O
and	O
user	B-Application
interface	I-Application
,	O
and	O
the	O
structured	O
development	O
process	O
with	O
less	O
implementation	O
effort	O
.	O
</s>
<s>
This	O
leads	O
to	O
a	O
reduced	O
data	O
transfer	O
from	O
ABAP	B-Language
server	O
to	O
browser	O
and	O
vice	O
versa	O
.	O
</s>
<s>
Regarding	O
Web	B-Language
Dynpro	I-Language
ABAP	I-Language
there	O
is	O
only	O
one	O
programming	O
language	O
(	O
ABAP	B-Language
)	O
and	O
only	O
one	O
system	O
necessary	O
.	O
</s>
