<s>
Slack	B-Protocol
is	O
an	O
instant	B-Application
messaging	I-Application
program	O
designed	O
by	O
Slack	B-Protocol
Technologies	O
and	O
owned	O
by	O
Salesforce	B-Application
.	O
</s>
<s>
Although	O
Slack	B-Protocol
was	O
developed	O
for	O
professional	O
and	O
organizational	O
communications	O
,	O
it	O
has	O
also	O
been	O
adopted	O
as	O
a	O
community	O
platform	O
.	O
</s>
<s>
Users	O
can	O
communicate	O
with	O
voice	B-Application
calls	I-Application
,	O
video	B-Application
calls	I-Application
,	O
text	O
messaging	O
,	O
media	O
,	O
and	O
files	O
in	O
private	O
chats	O
or	O
as	O
part	O
of	O
communities	O
called	O
"	O
workspaces.	O
"	O
</s>
<s>
Slack	B-Protocol
also	O
uses	O
IRC-style	O
features	O
such	O
as	O
persistent	B-Protocol
chat	I-Protocol
rooms	O
(	O
channels	O
)	O
organized	O
by	O
topic	O
,	O
private	O
groups	O
,	O
and	O
direct	O
messaging	O
.	O
</s>
<s>
In	O
addition	O
to	O
these	O
online	O
communication	O
features	O
,	O
Slack	B-Protocol
can	O
integrate	O
with	O
other	O
software	O
.	O
</s>
<s>
Slack	B-Protocol
runs	O
on	O
Web	O
,	O
Windows	O
,	O
Linux	B-Application
,	O
MacOS	B-Application
,	O
Android	B-Application
,	O
Windows	B-Protocol
Phone	I-Protocol
and	O
iOS	B-Application
.	O
</s>
<s>
Slack	B-Protocol
began	O
as	O
an	O
internal	O
tool	O
for	O
Stewart	O
Butterfield	O
's	O
company	O
,	O
Tiny	O
Speck	O
,	O
during	O
the	O
development	O
of	O
Glitch	B-Application
,	O
an	O
online	O
game	O
.	O
</s>
<s>
Slack	B-Protocol
launched	O
to	O
the	O
public	O
in	O
August	O
2013	O
.	O
</s>
<s>
According	O
to	O
Butterfield	O
,	O
"	O
Slack	B-Protocol
"	O
is	O
an	O
acronym	O
for	O
"	O
Searchable	B-Protocol
Log	I-Protocol
of	I-Protocol
All	I-Protocol
Conversation	I-Protocol
and	I-Protocol
Knowledge	I-Protocol
,	O
"	O
which	O
he	O
chose	O
in	O
2012	O
to	O
replace	O
the	O
previous	O
codename	O
,	O
"	O
linefeed.	O
"	O
</s>
<s>
Slack	B-Protocol
was	O
previously	O
compatible	O
with	O
non-proprietary	O
Internet	B-Protocol
Relay	I-Protocol
Chat	I-Protocol
(	O
IRC	B-Protocol
)	O
and	O
XMPP	B-Protocol
messaging	O
protocols	O
,	O
but	O
the	O
company	O
closed	O
the	O
corresponding	O
gateways	O
in	O
May	O
2018	O
.	O
</s>
<s>
On	O
July	O
26	O
,	O
2018	O
,	O
Atlassian	O
announced	O
the	O
shutdown	O
of	O
its	O
competing	O
HipChat	B-Protocol
and	O
Stride	B-Protocol
,	O
effective	O
February	O
11	O
,	O
2019	O
,	O
and	O
the	O
sale	O
of	O
its	O
intellectual	O
property	O
to	O
Slack	B-Protocol
.	O
</s>
<s>
The	O
companies	O
also	O
announced	O
a	O
commitment	O
to	O
work	O
on	O
integrating	O
Slack	B-Protocol
with	O
Atlassian	O
services	O
.	O
</s>
<s>
In	O
June	O
2019	O
,	O
Slack	B-Protocol
went	O
public	O
through	O
a	O
direct	O
public	O
offering	O
to	O
reach	O
a	O
market	O
value	O
of	O
US	O
$19.5	O
billion	O
.	O
</s>
<s>
In	O
July	O
2020	O
,	O
Slack	B-Protocol
acquired	O
Rimeto	O
;	O
a	O
startup	O
company	O
focused	O
on	O
directory	O
building	O
.	O
</s>
<s>
This	O
acquisition	O
was	O
to	O
provide	O
additional	O
search	O
offerings	O
for	O
employees	O
within	O
a	O
Slack	B-Protocol
workspace	O
.	O
</s>
<s>
On	O
January	O
1	O
,	O
2021	O
,	O
Slack	B-Protocol
and	O
Salesforce	B-Application
announced	O
an	O
agreement	O
for	O
Salesforce	B-Application
to	O
acquire	O
the	O
company	O
for	O
a	O
value	O
of	O
approximately	O
$27.7	O
billion	O
.	O
</s>
<s>
On	O
December	O
5	O
,	O
2022	O
,	O
Salesforce	B-Application
announced	O
that	O
Stewart	O
Butterfield	O
was	O
leaving	O
Slack	B-Protocol
,	O
and	O
he	O
would	O
be	O
succeeded	O
by	O
Lidiane	O
Jones	O
,	O
an	O
executive	O
vice	O
president	O
at	O
Salesforce	B-Application
.	O
</s>
<s>
In	O
March	O
2015	O
,	O
Slack	B-Protocol
announced	O
it	O
had	O
been	O
hacked	O
for	O
over	O
four	O
days	O
in	O
February	O
2015	O
and	O
that	O
some	O
data	O
associated	O
with	O
user	O
accounts	O
had	O
been	O
compromised	O
,	O
including	O
email	O
addresses	O
,	O
usernames	O
,	O
hashed	O
passwords	O
,	O
phone	O
numbers	O
,	O
and	O
Skype	B-Application
IDs	O
.	O
</s>
<s>
In	O
response	O
to	O
the	O
attacks	O
,	O
Slack	B-Protocol
added	O
two-factor	O
authentication	O
to	O
its	O
service	O
.	O
</s>
<s>
On	O
January	O
4	O
,	O
2021	O
,	O
Slack	B-Protocol
suffered	O
a	O
significant	O
outage	O
that	O
lasted	O
several	O
hours	O
.	O
</s>
<s>
From	O
10	O
AM	O
ET	O
until	O
3	O
PM	O
ET	O
,	O
users	O
could	O
not	O
log	O
in	O
,	O
send	O
or	O
receive	O
messages	O
,	O
place	O
or	O
answer	O
calls	O
,	O
or	O
use	O
Slack	B-Protocol
connections	O
.	O
</s>
<s>
After	O
3	O
PM	O
,	O
most	O
of	O
the	O
core	O
features	O
became	O
operational	O
,	O
except	O
for	O
push	O
notifications	O
,	O
email	O
,	O
and	O
third-party	O
integrations	O
including	O
Google	B-Application
Calendar	I-Application
and	O
Outlook	B-Operating_System
Calendar	I-Operating_System
.	O
</s>
<s>
In	O
2022	O
,	O
Slack	B-Protocol
suffered	O
widely	O
reported	O
outages	O
on	O
February	O
22	O
,	O
March	O
9	O
,	O
July	O
26	O
.	O
</s>
<s>
On	O
31	O
December	O
2022	O
,	O
Slack	B-Protocol
announced	O
that	O
its	O
private	O
GitHub	B-Application
repositories	O
had	O
been	O
compromised	O
during	O
previous	O
weeks	O
,	O
using	O
stolen	O
security	O
tokens	O
.	O
</s>
<s>
Slack	B-Protocol
offers	O
many	O
IRC-style	O
features	O
,	O
including	O
persistent	B-Protocol
chat	I-Protocol
rooms	O
(	O
channels	O
)	O
organized	O
by	O
topic	O
,	O
private	O
groups	O
,	O
and	O
direct	O
messaging	O
.	O
</s>
<s>
Content	O
,	O
including	O
files	O
,	O
conversations	O
,	O
and	O
people	O
,	O
is	O
all	O
searchable	O
within	O
Slack	B-Protocol
.	O
</s>
<s>
Users	O
can	O
add	O
emoji	B-Application
buttons	O
to	O
their	O
messages	O
,	O
which	O
other	O
users	O
can	O
then	O
click	O
to	O
express	O
their	O
reactions	O
to	O
messages	O
.	O
</s>
<s>
Slack	B-Protocol
's	O
free	O
plan	O
limits	O
users	O
to	O
viewing	O
and	O
searching	O
only	O
the	O
most	O
recent	O
10,000	O
messages	O
.	O
</s>
<s>
In	O
March	O
2020	O
,	O
Slack	B-Protocol
redesigned	O
its	O
platform	O
in	O
an	O
attempt	O
to	O
further	O
simplify	O
the	O
user	O
experience	O
.	O
</s>
<s>
Slack	B-Protocol
teams	O
allow	O
communities	O
,	O
groups	O
,	O
or	O
teams	O
to	O
join	O
a	O
"	O
workspace	O
"	O
via	O
a	O
specific	O
URL	O
or	O
invitation	O
sent	O
by	O
a	O
team	O
admin	O
or	O
owner	O
.	O
</s>
<s>
Although	O
Slack	B-Protocol
was	O
developed	O
for	O
professional	O
and	O
organizational	O
communications	O
,	O
it	O
has	O
been	O
adopted	O
as	O
a	O
social-community	O
platform	O
.	O
</s>
<s>
Public	O
channels	O
allow	O
team	O
members	O
to	O
communicate	O
without	O
the	O
use	O
of	O
email	O
or	O
group	O
SMS	B-Device
(	O
texting	O
)	O
.	O
</s>
<s>
In	O
March	O
2022	O
,	O
Slack	B-Protocol
announced	O
Huddles	O
,	O
"	O
a	O
lightweight	O
audio-first	O
way	O
to	O
start	O
live	O
conversations	O
,	O
"	O
which	O
TNW	O
described	O
as	O
"	O
effectively	O
a	O
Clubhouse	B-Application
clone	O
"	O
after	O
it	O
was	O
first	O
launched	O
in	O
2021	O
.	O
</s>
<s>
Slack	B-Protocol
integrates	O
with	O
many	O
third-party	O
services	O
and	O
supports	O
community-built	O
integrations	O
,	O
including	O
Google	B-Application
Drive	I-Application
,	O
Trello	B-Application
,	O
Dropbox	B-Application
,	O
Box	O
,	O
Heroku	B-General_Concept
,	O
IBM	B-General_Concept
Bluemix	I-General_Concept
,	O
Crashlytics	B-Application
,	O
GitHub	B-Application
,	O
Runscope	B-Application
,	O
Zendesk	O
,	O
and	O
Zapier	B-Application
.	O
</s>
<s>
In	O
July	O
2015	O
,	O
Slack	B-Protocol
launched	O
an	O
integration	O
with	O
Google	B-Application
Calendar	I-Application
.	O
</s>
<s>
In	O
December	O
of	O
that	O
year	O
,	O
Slack	B-Protocol
launched	O
their	O
software	B-Application
application	I-Application
(	O
"	O
app	O
"	O
)	O
directory	O
,	O
consisting	O
of	O
over	O
150	O
integrations	O
that	O
users	O
can	O
install	O
.	O
</s>
<s>
In	O
March	O
2018	O
,	O
Slack	B-Protocol
announced	O
a	O
partnership	O
with	O
a	O
financial	O
and	O
human	O
capital	O
management	O
firm	O
Workday	B-Application
.	O
</s>
<s>
This	O
integration	O
allows	O
Workday	B-Application
customers	O
to	O
access	O
Workday	B-Application
features	O
directly	O
from	O
the	O
Slack	B-Protocol
interface	O
.	O
</s>
<s>
Slack	B-Protocol
provides	O
an	O
application	B-Application
programming	I-Application
interface	I-Application
(	O
API	B-Application
)	O
for	O
users	O
to	O
create	O
applications	O
and	O
automate	O
processes	O
,	O
such	O
as	O
sending	O
automatic	O
notifications	O
based	O
on	O
human	O
input	O
,	O
sending	O
alerts	O
on	O
specified	O
conditions	O
,	O
and	O
automatically	O
creating	O
internal	O
support	O
tickets	O
.	O
</s>
<s>
Slack	B-Protocol
's	O
API	B-Application
is	O
compatible	O
with	O
many	O
types	O
of	O
applications	O
,	O
frameworks	B-Application
,	O
and	O
services	O
.	O
</s>
<s>
Slack	B-Protocol
allows	O
users	O
to	O
add	O
and	O
customize	O
chatbots	B-Application
,	O
which	O
can	O
send	O
notifications	O
or	O
reminders	O
,	O
provide	O
custom	O
responses	O
to	O
specific	O
phrases	O
,	O
etc	O
.	O
</s>
<s>
Slack	B-Protocol
provides	O
mobile	O
apps	O
for	O
iOS	B-Application
and	O
Android	B-Application
in	O
addition	O
to	O
their	O
Web	O
browser	O
client	O
and	O
desktop	O
clients	O
for	O
MacOS	B-Application
,	O
Windows	O
,	O
and	O
Linux	B-Application
(	O
beta	O
)	O
.	O
</s>
<s>
Slack	B-Protocol
is	O
also	O
available	O
for	O
the	O
Apple	B-Device
Watch	I-Device
,	O
allowing	O
users	O
to	O
send	O
direct	O
messages	O
,	O
see	O
mentions	O
,	O
and	O
make	O
simple	O
replies	O
.	O
</s>
<s>
Slack	B-Protocol
has	O
been	O
made	O
to	O
run	O
on	O
a	O
Super	B-Application
Nintendo	I-Application
Entertainment	I-Application
System	I-Application
via	O
Satellaview	B-Device
.	O
</s>
<s>
Slack	B-Protocol
is	O
a	O
freemium	O
product	O
whose	O
main	O
paid	O
features	O
are	O
the	O
ability	O
to	O
search	O
more	O
than	O
10,000	O
archived	O
messages	O
and	O
add	O
unlimited	O
apps	O
and	O
integrations	O
.	O
</s>
<s>
When	O
FreeCodeCamp	B-Application
attempted	O
to	O
switch	O
its	O
community	O
of	O
over	O
8,000	O
users	O
to	O
Slack	B-Protocol
in	O
2015	O
,	O
however	O
,	O
they	O
experienced	O
many	O
technical	O
issues	O
and	O
were	O
advised	O
by	O
Slack	B-Protocol
support	O
to	O
limit	O
their	O
channels	O
to	O
"	O
no	O
more	O
than	O
1,000	O
users	O
(	O
ideally	O
more	O
like	O
500	O
)	O
.	O
"	O
</s>
<s>
Late	O
in	O
2015	O
,	O
Slack	B-Protocol
passed	O
more	O
than	O
a	O
million	O
daily	O
active	O
users	O
.	O
</s>
<s>
,	O
Slack	B-Protocol
had	O
over	O
8	O
million	O
daily	O
users	O
,	O
3	O
million	O
of	O
whom	O
had	O
paid	O
accounts	O
.	O
</s>
<s>
At	O
the	O
time	O
of	O
its	O
S-1	O
filing	O
for	O
IPO	O
,	O
dated	O
April	O
26	O
,	O
2019	O
,	O
Slack	B-Protocol
reported	O
more	O
than	O
10	O
million	O
daily	O
active	O
users	O
from	O
more	O
than	O
600,000	O
organizations	O
,	O
located	O
in	O
more	O
than	O
150	O
countries	O
.	O
</s>
<s>
In	O
2019	O
,	O
it	O
was	O
estimated	O
that	O
employees	O
at	O
large	O
firms	O
were	O
sending	O
over	O
200	O
Slack	B-Protocol
messages	O
per	O
week	O
on	O
average	O
.	O
</s>
<s>
From	O
2013	O
to	O
2019	O
the	O
amount	O
of	O
time	O
spent	O
on	O
work	O
email	O
had	O
declined	O
,	O
which	O
was	O
attributed	O
to	O
the	O
proliferation	O
of	O
Slack	B-Protocol
and	O
its	O
competitors	O
Workplace	B-Application
(	O
launched	O
by	O
Facebook	O
in	O
2016	O
)	O
,	O
Microsoft	B-Application
Teams	I-Application
(	O
launched	O
2017	O
)	O
and	O
Google	B-Application
Hangouts	I-Application
Chat	I-Application
and	O
Meet	O
(	O
launched	O
in	O
2018	O
)	O
.	O
</s>
<s>
In	O
March	O
2015	O
,	O
the	O
Financial	O
Times	O
wrote	O
that	O
Slack	B-Protocol
was	O
the	O
first	O
business	O
technology	O
to	O
have	O
crossed	O
from	O
business	O
into	O
personal	O
use	O
since	O
Microsoft	B-Application
Office	I-Application
and	O
the	O
BlackBerry	B-Operating_System
.	O
</s>
<s>
In	O
2017	O
,	O
Slack	B-Protocol
was	O
recognized	O
as	O
the	O
best	O
startup	O
of	O
the	O
year	O
at	O
the	O
Crunchies	O
Awards	O
,	O
organized	O
by	O
TechCrunch	O
.	O
</s>
<s>
The	O
digital	O
rights	O
group	O
Electronic	O
Frontier	O
Foundation	O
(	O
EFF	O
)	O
has	O
cautioned	O
that	O
"	O
Slack	B-Protocol
stores	O
and	O
is	O
able	O
to	O
read	O
all	O
of	O
your	O
communications	O
,	O
as	O
well	O
as	O
identifying	O
information	O
for	O
everyone	O
in	O
your	O
workspace.	O
"	O
</s>
<s>
They	O
commended	O
the	O
company	O
for	O
"follow[ing]	O
several	O
best	O
practices	O
in	O
standing	O
up	O
for	O
users	O
"	O
concerning	O
government	O
data	O
requests	O
,	O
such	O
as	O
requiring	O
a	O
warrant	O
for	O
content	O
stored	O
on	O
its	O
server	O
,	O
and	O
awarding	O
it	O
four	O
out	O
of	O
five	O
stars	O
in	O
its	O
2017	O
"	O
Who	O
has	O
your	O
back	O
"	O
report	O
;	O
the	O
EFF	O
also	O
criticized	O
Slack	B-Protocol
for	O
"	O
a	O
broad	O
set	O
of	O
exceptions	O
"	O
to	O
its	O
promise	O
to	O
notify	O
users	O
of	O
such	O
requests	O
,	O
and	O
for	O
other	O
privacy	O
shortcomings	O
.	O
</s>
<s>
Slack	B-Protocol
has	O
been	O
criticized	O
by	O
users	O
for	O
storing	O
user	O
data	O
exclusively	O
on	O
cloud	B-Architecture
servers	O
under	O
Slack	B-Protocol
control	O
.	O
</s>
<s>
Slack	B-Protocol
has	O
also	O
been	O
criticized	O
for	O
a	O
retroactive	O
2018	O
change	O
to	O
its	O
privacy	O
policy	O
,	O
allowing	O
access	O
to	O
all	O
public	O
and	O
private	O
chat	O
messages	O
by	O
workspace	O
administrators	O
,	O
without	O
the	O
need	O
of	O
consent	O
from	O
any	O
parties	O
using	O
the	O
app	O
.	O
</s>
<s>
According	O
to	O
the	O
new	O
policy	O
,	O
Slack	B-Protocol
workspace	O
members	O
are	O
no	O
longer	O
notified	O
when	O
data	O
is	O
downloaded	O
from	O
their	O
workspace	O
.	O
</s>
<s>
Slack	B-Protocol
has	O
also	O
been	O
criticized	O
when	O
used	O
in	O
free	O
and	O
open	O
source	O
projects	O
for	O
the	O
inability	O
to	O
search	O
for	O
messages	O
and	O
discussions	O
.	O
</s>
<s>
However	O
,	O
Slack	B-Protocol
channels	O
are	O
not	O
indexed	O
by	O
search	O
engines	O
,	O
so	O
they	O
cannot	O
be	O
searched	O
using	O
traditional	O
tools	O
.	O
</s>
