<s>
In	O
computing	O
,	O
an	O
applet	B-Language
is	O
any	O
small	O
application	B-Application
that	O
performs	O
one	O
specific	O
task	O
that	O
runs	O
within	O
the	O
scope	O
of	O
a	O
dedicated	O
widget	O
engine	O
or	O
a	O
larger	O
program	B-Application
,	O
often	O
as	O
a	O
plug-in	B-Application
.	O
</s>
<s>
The	O
term	O
is	O
frequently	O
used	O
to	O
refer	O
to	O
a	O
Java	B-Application
applet	I-Application
,	O
a	O
program	B-Application
written	O
in	O
the	O
Java	B-Language
programming	I-Language
language	I-Language
that	O
is	O
designed	O
to	O
be	O
placed	O
on	O
a	O
web	O
page	O
.	O
</s>
<s>
Applets	B-Language
are	O
typical	O
examples	O
of	O
transient	B-General_Concept
and	I-General_Concept
auxiliary	I-General_Concept
applications	I-General_Concept
that	O
do	O
n't	O
monopolize	O
the	O
user	O
's	O
attention	O
.	O
</s>
<s>
Applets	B-Language
are	O
not	O
full-featured	O
application	B-Application
programs	I-Application
,	O
and	O
are	O
intended	O
to	O
be	O
easily	O
accessible	O
.	O
</s>
<s>
The	O
word	O
applet	B-Language
was	O
first	O
used	O
in	O
1990	O
in	O
PC	O
Magazine	O
.	O
</s>
<s>
However	O
,	O
the	O
concept	O
of	O
an	O
applet	B-Language
,	O
or	O
more	O
broadly	O
a	O
small	O
interpreted	O
program	B-Application
downloaded	O
and	O
executed	O
by	O
the	O
user	O
,	O
dates	O
at	O
least	O
to	O
RFC	O
5	O
(	O
1969	O
)	O
by	O
Jeff	O
Rulifson	O
,	O
which	O
described	O
the	O
Decode-Encode	O
Language	O
,	O
which	O
was	O
designed	O
to	O
allow	O
remote	O
use	O
of	O
the	O
oN-Line	O
System	O
over	O
ARPANET	O
,	O
by	O
downloading	O
small	O
programs	O
to	O
enhance	O
the	O
interaction	O
.	O
</s>
<s>
This	O
has	O
been	O
specifically	O
credited	O
as	O
a	O
forerunner	O
of	O
Java	B-Language
's	O
downloadable	O
programs	O
in	O
RFC	O
2555	O
.	O
</s>
<s>
In	O
some	O
cases	O
,	O
an	O
applet	B-Language
does	O
not	O
run	O
independently	O
.	O
</s>
<s>
These	O
applets	B-Language
must	O
run	O
either	O
in	O
a	O
container	B-Application
provided	O
by	O
a	O
host	O
program	B-Application
,	O
through	O
a	O
plugin	B-Application
,	O
or	O
a	O
variety	O
of	O
other	O
applications	O
including	O
mobile	O
devices	O
that	O
support	O
the	O
applet	B-Language
programming	O
model	O
.	O
</s>
<s>
Applets	B-Language
were	O
used	O
to	O
provide	O
interactive	O
features	O
to	O
web	O
applications	O
that	O
historically	O
could	O
not	O
be	O
provided	O
by	O
HTML	B-Language
alone	O
.	O
</s>
<s>
They	O
could	O
capture	O
mouse	B-Device
input	I-Device
and	O
also	O
had	O
controls	O
like	O
buttons	O
or	O
check	O
boxes	O
.	O
</s>
<s>
In	O
response	O
to	O
the	O
user	O
action	O
,	O
an	O
applet	B-Language
could	O
change	O
the	O
provided	O
graphic	O
content	O
.	O
</s>
<s>
This	O
made	O
applets	B-Language
well	O
suited	O
for	O
demonstration	O
,	O
visualization	O
,	O
and	O
teaching	O
.	O
</s>
<s>
There	O
were	O
online	O
applet	B-Language
collections	O
for	O
studying	O
various	O
subjects	O
,	O
from	O
physics	O
to	O
heart	O
physiology	O
.	O
</s>
<s>
Applets	B-Language
were	O
also	O
used	O
to	O
create	O
online	O
game	O
collections	O
that	O
allowed	O
players	O
to	O
compete	O
against	O
live	O
opponents	O
in	O
real-time	O
.	O
</s>
<s>
An	O
applet	B-Language
could	O
also	O
be	O
a	O
text	O
area	O
only	O
,	O
providing	O
,	O
for	O
instance	O
,	O
a	O
cross-platform	O
command-line	B-Application
interface	I-Application
to	O
some	O
remote	O
system	O
.	O
</s>
<s>
If	O
needed	O
,	O
an	O
applet	B-Language
could	O
leave	O
the	O
dedicated	O
area	O
and	O
run	O
as	O
a	O
separate	O
window	O
.	O
</s>
<s>
However	O
,	O
applets	B-Language
had	O
very	O
little	O
control	O
over	O
web	O
page	O
content	O
outside	O
the	O
applet	B-Language
dedicated	O
area	O
,	O
so	O
they	O
were	O
less	O
useful	O
for	O
improving	O
the	O
site	O
appearance	O
in	O
general	O
(	O
while	O
applets	B-Language
like	O
news	O
tickers	O
or	O
WYSIWYG	B-Application
editors	I-Application
are	O
also	O
known	O
)	O
.	O
</s>
<s>
Applets	B-Language
could	O
also	O
play	O
media	O
in	O
formats	O
that	O
are	O
not	O
natively	O
supported	O
by	O
the	O
browser	B-Application
.	O
</s>
<s>
HTML	B-Language
pages	O
could	O
embed	O
parameters	O
that	O
were	O
passed	O
to	O
the	O
applet	B-Language
.	O
</s>
<s>
Hence	O
,	O
the	O
same	O
applet	B-Language
could	O
appear	O
differently	O
depending	O
on	O
the	O
parameters	O
that	O
were	O
passed	O
.	O
</s>
<s>
Examples	O
of	O
Web-based	O
applets	B-Language
include	O
:	O
</s>
<s>
Browser	B-Protocol
games	I-Protocol
that	O
were	O
applet-based	O
,	O
though	O
some	O
developed	O
into	O
fully	O
functional	O
applications	O
that	O
required	O
installation	O
.	O
</s>
<s>
A	O
larger	O
application	B-Application
distinguishes	O
its	O
applets	B-Language
through	O
several	O
features	O
:	O
</s>
<s>
Applets	B-Language
execute	O
only	O
on	O
the	O
"	O
client	O
"	O
platform	O
environment	O
of	O
a	O
system	O
,	O
as	O
contrasted	O
from	O
"	O
Servlet	B-Application
"	O
.	O
</s>
<s>
As	O
such	O
,	O
an	O
applet	B-Language
provides	O
functionality	O
or	O
performance	O
beyond	O
the	O
default	O
capabilities	O
of	O
its	O
container	B-Application
(	O
the	O
browser	B-Application
)	O
.	O
</s>
<s>
The	O
container	B-Application
restricts	O
applets	B-Language
 '	O
capabilities	O
.	O
</s>
<s>
Applets	B-Language
are	O
written	O
in	O
a	O
language	O
different	O
from	O
the	O
scripting	O
or	O
HTML	B-Language
language	I-Language
that	O
invokes	O
it	O
.	O
</s>
<s>
The	O
applet	B-Language
is	O
written	O
in	O
a	O
compiled	O
language	O
,	O
whereas	O
the	O
scripting	O
language	O
of	O
the	O
container	B-Application
is	O
an	O
interpreted	O
language	O
,	O
hence	O
the	O
greater	O
performance	O
or	O
functionality	O
of	O
the	O
applet	B-Language
.	O
</s>
<s>
Unlike	O
a	O
subroutine	O
,	O
a	O
complete	O
web	O
component	O
can	O
be	O
implemented	O
as	O
an	O
applet	B-Language
.	O
</s>
<s>
A	O
Java	B-Application
applet	I-Application
is	O
a	O
Java	B-Language
program	B-Application
that	O
is	O
launched	O
from	O
HTML	B-Language
and	O
run	O
in	O
a	O
web	B-Application
browser	I-Application
.	O
</s>
<s>
It	O
takes	O
code	O
from	O
server	O
and	O
run	O
in	O
a	O
web	B-Application
browser	I-Application
.	O
</s>
<s>
It	O
can	O
provide	O
web	O
applications	O
with	O
interactive	O
features	O
that	O
cannot	O
be	O
provided	O
by	O
HTML	B-Language
.	O
</s>
<s>
Since	O
Java	B-Language
's	O
bytecode	O
is	O
platform-independent	O
,	O
Java	B-Application
applets	I-Application
can	O
be	O
executed	O
by	O
browsers	B-Application
running	O
under	O
many	O
platforms	O
,	O
including	O
Windows	B-Application
,	O
Unix	B-Application
,	O
macOS	B-Application
,	O
and	O
Linux	B-Application
.	O
</s>
<s>
When	O
a	O
Java	O
technology-enabled	O
web	B-Application
browser	I-Application
processes	O
a	O
page	O
that	O
contains	O
an	O
applet	B-Language
,	O
the	O
applet	B-Language
's	O
code	O
is	O
transferred	O
to	O
the	O
client	O
's	O
system	O
and	O
executed	O
by	O
the	O
browser	B-Application
's	O
Java	B-Language
virtual	I-Language
machine	I-Language
.	O
</s>
<s>
An	O
HTML	B-Language
page	O
references	O
an	O
applet	B-Language
either	O
via	O
the	O
deprecated	B-General_Concept
tag	O
or	O
via	O
its	O
replacement	O
,	O
the	O
tag	O
.	O
</s>
<s>
Recent	O
developments	O
in	O
the	O
coding	O
of	O
applications	O
,	O
including	O
mobile	O
and	O
embedded	B-Architecture
systems	I-Architecture
,	O
have	O
led	O
to	O
the	O
awareness	O
of	O
the	O
security	O
of	O
applets	B-Language
.	O
</s>
<s>
Applets	B-Language
in	O
an	O
open	B-Application
platform	I-Application
environment	O
should	O
provide	O
secure	O
interactions	O
between	O
different	O
applications	O
.	O
</s>
<s>
A	O
compositional	O
approach	O
can	O
be	O
used	O
to	O
provide	O
security	O
for	O
open	B-Application
platform	I-Application
applets	B-Language
.	O
</s>
<s>
Advanced	O
compositional	O
verification	O
methods	O
have	O
been	O
developed	O
for	O
secure	O
applet	B-Language
interactions	O
.	O
</s>
<s>
A	O
Java	B-Application
applet	I-Application
contains	O
different	O
security	O
models	O
:	O
unsigned	O
Java	B-Application
applet	I-Application
security	O
,	O
signed	O
Java	B-Application
applet	I-Application
security	O
,	O
and	O
self-signed	O
Java	B-Application
applet	I-Application
security	O
.	O
</s>
<s>
In	O
an	O
applet-enabled	O
web	B-Application
browser	I-Application
,	O
many	O
methods	O
can	O
be	O
used	O
to	O
provide	O
applet	B-Language
security	O
for	O
malicious	O
applets	B-Language
.	O
</s>
<s>
A	O
malicious	O
applet	B-Language
can	O
infect	O
a	O
computer	O
system	O
in	O
many	O
ways	O
,	O
including	O
denial	O
of	O
service	O
,	O
invasion	O
of	O
privacy	O
,	O
and	O
annoyance	O
.	O
</s>
<s>
A	O
typical	O
solution	O
for	O
malicious	O
applets	B-Language
is	O
to	O
make	O
the	O
web	B-Application
browser	I-Application
to	O
monitor	O
applets	B-Language
 '	O
activities	O
.	O
</s>
<s>
This	O
will	O
result	O
in	O
a	O
web	B-Application
browser	I-Application
that	O
will	O
enable	O
the	O
manual	O
or	O
automatic	O
stopping	O
of	O
malicious	O
applets	B-Language
.	O
</s>
