<s>
Software	B-Application
deployment	I-Application
is	O
all	O
of	O
the	O
activities	O
that	O
make	O
a	O
software	O
system	O
available	O
for	O
use	O
.	O
</s>
<s>
These	O
activities	O
can	O
occur	O
on	O
the	O
producer	B-Application
side	O
or	O
on	O
the	O
consumer	O
side	O
or	O
both	O
.	O
</s>
<s>
Because	O
every	O
software	O
system	O
is	O
unique	O
,	O
the	O
precise	O
processes	B-Operating_System
or	O
procedures	O
within	O
each	O
activity	O
can	O
hardly	O
be	O
defined	O
.	O
</s>
<s>
When	O
computers	O
were	O
extremely	O
large	O
,	O
expensive	O
,	O
and	O
bulky	O
(	O
mainframes	B-Architecture
and	O
minicomputers	B-Architecture
)	O
,	O
the	O
software	O
was	O
often	O
bundled	O
together	O
with	O
the	O
hardware	O
by	O
manufacturers	O
.	O
</s>
<s>
If	O
business	B-Application
software	I-Application
needed	O
to	O
be	O
installed	O
on	O
an	O
existing	O
computer	O
,	O
this	O
might	O
require	O
an	O
expensive	O
,	O
time-consuming	O
visit	O
by	O
a	O
systems	O
architect	O
or	O
a	O
consultant	O
.	O
</s>
<s>
For	O
complex	O
,	O
on-premises	O
installation	B-Application
of	O
enterprise	B-Application
software	I-Application
today	O
,	O
this	O
can	O
still	O
sometimes	O
be	O
the	O
case	O
.	O
</s>
<s>
However	O
,	O
with	O
the	O
development	O
of	O
mass-market	O
software	O
for	O
the	O
new	O
age	O
of	O
microcomputers	B-Architecture
in	O
the	O
1980s	O
came	O
new	O
forms	O
of	O
software	B-Application
distribution	I-Application
first	O
cartridges	B-Protocol
,	O
then	O
Compact	O
Cassettes	O
,	O
then	O
floppy	B-Device
disks	I-Device
,	O
then	O
(	O
in	O
the	O
1990s	O
and	O
later	O
)	O
optical	B-Device
media	I-Device
,	O
the	O
internet	O
and	O
flash	O
drives	O
.	O
</s>
<s>
This	O
meant	O
that	O
software	B-Application
deployment	I-Application
could	O
be	O
left	O
to	O
the	O
customer	O
.	O
</s>
<s>
In	O
pre-internet	O
software	B-Application
deployments	I-Application
,	O
deployments	O
(	O
and	O
their	O
closely	O
related	O
cousin	O
,	O
new	O
software	O
releases	O
)	O
were	O
of	O
necessity	O
expensive	O
,	O
infrequent	O
,	O
bulky	O
affairs	O
.	O
</s>
<s>
Indeed	O
,	O
the	O
advent	O
of	O
cloud	B-Architecture
computing	I-Architecture
and	O
software	B-Architecture
as	I-Architecture
a	I-Architecture
service	I-Architecture
meant	O
that	O
software	O
could	O
be	O
deployed	O
to	O
a	O
large	O
number	O
of	O
customers	O
in	O
minutes	O
,	O
over	O
the	O
internet	O
.	O
</s>
<s>
Such	O
flexibility	O
led	O
to	O
the	O
rise	O
of	O
continuous	O
delivery	O
as	O
a	O
viable	O
option	O
,	O
especially	O
for	O
less	O
risky	O
web	B-Application
applications	I-Application
.	O
</s>
<s>
It	O
includes	O
all	O
the	O
operations	O
to	O
prepare	O
a	O
system	O
for	O
assembly	B-Language
and	O
transfer	O
to	O
the	O
computer	O
system(s )	O
on	O
which	O
it	O
will	O
be	O
run	O
in	O
production	O
.	O
</s>
<s>
Therefore	O
,	O
it	O
sometimes	O
involves	O
determining	O
the	O
resources	B-General_Concept
required	O
for	O
the	O
system	O
to	O
operate	O
with	O
tolerable	O
performance	O
and	O
planning	O
and/or	O
documenting	O
subsequent	O
activities	O
of	O
the	O
deployment	O
process	O
.	O
</s>
<s>
Installation	B-Application
and	O
activation	O
For	O
simple	O
systems	O
,	O
installation	B-Application
involves	O
establishing	O
some	O
form	O
of	O
a	O
command	B-Application
,	O
shortcut	O
,	O
script	O
or	O
service	O
for	O
executing	O
the	O
software	O
(	O
manually	O
or	O
automatically	O
)	O
.	O
</s>
<s>
Activation	O
is	O
the	O
activity	O
of	O
starting	O
up	O
the	O
executable	B-Application
component	O
of	O
software	O
for	O
the	O
first	O
time	O
(	O
not	O
to	O
be	O
confused	O
with	O
the	O
common	O
use	O
of	O
the	O
term	O
activation	O
concerning	O
a	O
software	O
license	O
,	O
which	O
is	O
a	O
function	O
of	O
Digital	O
Rights	O
Management	O
systems	O
.	O
)	O
</s>
<s>
In	O
larger	O
software	B-Application
deployments	I-Application
on	O
servers	B-Application
,	O
the	O
main	O
copy	O
of	O
the	O
software	O
to	O
be	O
used	O
by	O
users	O
-	O
"	O
production	O
"	O
-	O
might	O
be	O
installed	O
on	O
a	O
production	O
server	O
in	O
a	O
production	O
environment	O
.	O
</s>
<s>
In	O
complex	O
continuous	O
delivery	O
environments	O
and/or	O
software	B-Architecture
as	I-Architecture
a	I-Architecture
service	I-Architecture
system	O
,	O
differently-configured	O
versions	O
of	O
the	O
system	O
might	O
even	O
exist	O
simultaneously	O
in	O
the	O
production	O
environment	O
for	O
different	O
internal	O
or	O
external	O
customers	O
(	O
this	O
is	O
known	O
as	O
a	O
multi-tenant	O
architecture	O
)	O
,	O
or	O
even	O
be	O
gradually	O
rolled	O
out	O
in	O
parallel	O
to	O
different	O
groups	O
of	O
customers	O
,	O
with	O
the	O
possibility	O
of	O
canceling	O
one	O
or	O
more	O
of	O
the	O
parallel	O
deployments	O
.	O
</s>
<s>
For	O
example	O
,	O
Twitter	B-Application
is	O
known	O
to	O
use	O
the	O
latter	O
approach	O
for	O
A/B	O
testing	O
of	O
new	O
features	O
and	O
user	B-Application
interface	I-Application
changes	O
.	O
</s>
<s>
A	O
"	O
hidden	O
live	O
"	O
group	O
can	O
also	O
be	O
created	O
within	O
a	O
production	O
environment	O
,	O
consisting	O
of	O
servers	B-Application
that	O
are	O
not	O
yet	O
connected	O
to	O
the	O
production	O
load	B-Application
balancer	I-Application
,	O
for	O
the	O
purposes	O
of	O
blue-green	B-Application
deployment	I-Application
.	O
</s>
<s>
The	O
practice	O
of	O
removing	O
infrequently	O
used	O
or	O
obsolete	O
systems	O
from	O
service	O
is	O
often	O
referred	O
to	O
as	O
application	B-Application
retirement	I-Application
or	O
application	B-Application
decommissioning	I-Application
.	O
</s>
<s>
Uninstallation	O
Uninstallation	O
is	O
the	O
inverse	O
of	O
installation	B-Application
.	O
</s>
<s>
It	O
may	O
also	O
involve	O
some	O
reconfiguration	O
of	O
other	O
software	O
systems	O
to	O
remove	O
the	O
uninstalled	O
system	O
's	O
dependencies	B-Application
.	O
</s>
<s>
It	O
commonly	O
consists	O
of	O
deactivation	O
followed	O
by	O
installation	B-Application
.	O
</s>
<s>
On	O
some	O
systems	O
,	O
such	O
as	O
on	O
Linux	B-Application
when	O
using	O
the	O
system	O
's	O
package	B-Application
manager	I-Application
,	O
the	O
old	O
version	O
of	O
a	O
software	O
application	O
is	O
typically	O
also	O
uninstalled	O
as	O
an	O
automatic	O
part	O
of	O
the	O
process	O
.	O
</s>
<s>
(	O
This	O
is	O
because	O
Linux	B-Application
package	B-Application
managers	I-Application
do	O
not	O
typically	O
support	O
installing	O
multiple	O
versions	O
of	O
a	O
software	O
application	O
at	O
the	O
same	O
time	O
unless	O
the	O
software	B-Application
package	I-Application
has	O
been	O
specifically	O
designed	O
to	O
work	B-Application
around	I-Application
this	O
limitation	O
.	O
)	O
</s>
<s>
Built-in	O
update	O
Mechanisms	O
for	O
installing	O
updates	O
are	O
built	O
into	O
some	O
software	O
systems	O
(	O
or	O
,	O
in	O
the	O
case	O
of	O
some	O
operating	O
systems	O
such	O
as	O
Linux	B-Application
,	O
Android	B-Application
and	O
iOS	B-Application
,	O
into	O
the	O
operating	O
system	O
itself	O
)	O
.	O
</s>
<s>
Automation	O
of	O
these	O
update	O
processes	B-Operating_System
ranges	O
from	O
fully	O
automatic	O
to	O
user-initiated	O
and	O
controlled	O
.	O
</s>
<s>
Norton	B-Application
Internet	I-Application
Security	I-Application
is	O
an	O
example	O
of	O
a	O
system	O
with	O
a	O
semi-automatic	O
method	O
for	O
retrieving	O
and	O
installing	O
updates	O
to	O
both	O
the	O
antivirus	O
definitions	O
and	O
other	O
components	O
of	O
the	O
system	O
.	O
</s>
<s>
For	O
example	O
:	O
The	O
Software	O
Catalog	O
stores	O
the	O
version	O
and	O
other	O
information	O
for	O
each	O
software	B-Application
package	I-Application
installed	O
on	O
a	O
local	O
system	O
.	O
</s>
<s>
On	O
Linux	B-Application
,	O
Android	B-Application
and	O
iOS	B-Application
this	O
process	O
is	O
even	O
easier	O
because	O
a	O
standardized	O
process	O
for	O
version	O
tracking	O
(	O
for	O
software	B-Application
packages	I-Application
installed	O
in	O
the	O
officially	O
supported	O
way	O
)	O
is	O
built	O
into	O
the	O
operating	O
system	O
,	O
so	O
no	O
separate	O
login	O
,	O
download	O
and	O
execute	O
steps	O
are	O
required	O
so	O
the	O
process	O
can	O
be	O
configured	O
to	O
be	O
fully	O
automated	O
.	O
</s>
<s>
Some	O
third-party	O
software	O
also	O
supports	O
automated	O
version	O
tracking	O
and	O
upgrading	O
for	O
certain	O
Windows	O
software	B-Application
packages	I-Application
.	O
</s>
<s>
For	O
desktop	O
systems	O
,	O
end-users	O
frequently	O
also	O
become	O
the	O
"	O
software	O
deployers	O
"	O
when	O
they	O
install	O
a	O
software	B-Application
package	I-Application
on	O
their	O
machine	O
.	O
</s>
<s>
The	O
deployment	O
of	O
enterprise	B-Application
software	I-Application
involves	O
many	O
more	O
roles	O
,	O
and	O
those	O
roles	O
typically	O
change	O
as	O
the	O
application	O
progresses	O
from	O
the	O
test	O
(	O
pre-production	O
)	O
to	O
production	O
environments	O
.	O
</s>
<s>
Typical	O
roles	O
involved	O
in	O
software	B-Application
deployments	I-Application
for	O
enterprise	B-Application
applications	I-Application
may	O
include	O
:	O
</s>
