<s>
Web	B-Protocol
browsing	I-Protocol
history	I-Protocol
refers	O
to	O
the	O
list	O
of	O
web	O
pages	O
a	O
user	O
has	O
visited	O
,	O
as	O
well	O
as	O
associated	O
metadata	O
such	O
as	O
page	O
title	O
and	O
time	O
of	O
visit	O
.	O
</s>
<s>
It	O
is	O
usually	O
stored	O
locally	O
by	O
web	B-Application
browsers	I-Application
in	O
order	O
to	O
provide	O
the	O
user	O
with	O
a	O
history	O
list	O
to	O
go	O
back	O
to	O
previously	O
visited	O
pages	O
.	O
</s>
<s>
All	O
major	O
browsers	B-Application
have	O
a	O
private	B-Protocol
browsing	I-Protocol
mode	O
in	O
which	O
browsing	B-Protocol
history	I-Protocol
is	O
not	O
recorded	O
.	O
</s>
<s>
Locally	O
stored	O
browsing	B-Protocol
history	I-Protocol
can	O
facilitate	O
rediscovering	O
lost	O
previously	O
visited	O
web	O
pages	O
of	O
which	O
one	O
only	O
has	O
a	O
vague	O
memory	O
in	O
mind	O
,	O
or	O
pages	O
difficult	O
to	O
find	O
due	O
to	O
being	O
located	O
within	O
deep	O
web	O
.	O
</s>
<s>
Browsers	B-Application
also	O
utilize	O
it	O
to	O
enable	O
autocompletion	O
in	O
their	O
address	O
bar	O
for	O
quicker	O
and	O
more	O
convenient	O
navigation	O
to	O
frequently	O
visited	O
pages	O
.	O
</s>
<s>
The	O
retention	O
span	O
of	O
browsing	B-Protocol
history	I-Protocol
varies	O
per	O
internet	B-Application
browser	I-Application
.	O
</s>
<s>
Mozilla	B-Application
Firefox	I-Application
(	O
desktop	O
version	O
)	O
records	O
history	O
indefinitely	O
by	O
default	O
inside	O
a	O
file	O
named	O
places.sqlite	O
,	O
but	O
automatically	O
erases	O
the	O
earliest	O
history	O
upon	O
exhausted	O
disk	O
space	O
,	O
while	O
Google	B-Application
Chrome	I-Application
(	O
desktop	O
version	O
)	O
stores	O
history	O
for	O
ten	O
weeks	O
by	O
default	O
,	O
automatically	O
pruning	O
earlier	O
entries	O
.	O
</s>
<s>
Browser	B-Protocol
extensions	I-Protocol
such	O
as	O
History	O
Trends	O
Unlimited	O
for	O
Google	B-Application
Chrome	I-Application
(	O
desktop	O
version	O
)	O
allow	O
the	O
indefinite	O
local	O
storage	O
of	O
browsing	B-Protocol
history	I-Protocol
,	O
exporting	B-General_Concept
into	O
a	O
portable	B-Application
file	I-Application
,	O
and	O
self-analysis	O
of	O
browsing	O
habits	O
and	O
statistics	O
.	O
</s>
<s>
Browsing	B-Protocol
history	I-Protocol
is	O
not	O
recorded	O
when	O
using	O
the	O
private	B-Protocol
browsing	I-Protocol
mode	O
provided	O
by	O
most	O
browsers	B-Application
.	O
</s>
<s>
Targeted	O
advertising	O
means	O
presenting	O
the	O
user	O
with	O
advertisements	O
that	O
are	O
more	O
relevant	O
to	O
one	O
based	O
on	O
one	O
's	O
browsing	B-Protocol
history	I-Protocol
.	O
</s>
<s>
The	O
information	O
of	O
users	O
,	O
such	O
as	O
browsing	B-Protocol
history	I-Protocol
,	O
is	O
provided	O
to	O
all	O
firms	O
that	O
are	O
involved	O
in	O
the	O
bidding	O
.	O
</s>
<s>
Web	B-Protocol
browsing	I-Protocol
history	I-Protocol
could	O
give	O
reliable	O
predictions	O
on	O
the	O
purchasing	O
behaviors	O
of	O
users	O
.	O
</s>
<s>
Web	B-Protocol
browsing	I-Protocol
history	I-Protocol
could	O
be	O
used	O
to	O
facilitate	O
research	O
,	O
such	O
as	O
revealing	O
the	O
browsing	O
behavior	O
of	O
people	O
.	O
</s>
<s>
Web	B-Protocol
browsing	I-Protocol
history	I-Protocol
could	O
also	O
be	O
used	O
to	O
create	O
personal	O
web	O
libraries	O
.	O
</s>
<s>
A	O
personal	O
web	O
library	O
is	O
created	O
by	O
collecting	O
and	O
analyzing	O
the	O
web	B-Protocol
browsing	I-Protocol
history	I-Protocol
of	O
the	O
user	O
.	O
</s>
<s>
Web	B-Protocol
browsing	I-Protocol
history	I-Protocol
stored	O
locally	O
is	O
not	O
published	O
anywhere	O
publicly	O
by	O
default	O
.	O
</s>
<s>
However	O
,	O
almost	O
all	O
the	O
websites	O
are	O
tracked	B-Application
by	O
adwares	O
and	O
potentially	B-Application
unwanted	I-Application
programs	I-Application
(	O
PUPs	O
)	O
which	O
collect	O
users	O
 '	O
information	O
without	O
their	O
consent	O
.	O
</s>
<s>
Web	B-Protocol
browsing	I-Protocol
history	I-Protocol
is	O
also	O
collected	O
by	O
cookies	B-Application
on	O
websites	O
,	O
which	O
could	O
be	O
divided	O
into	O
two	O
kinds	O
,	O
first-party	B-Application
cookies	I-Application
and	O
third-party	O
cookies	B-Application
.	O
</s>
<s>
Third-party	O
cookies	B-Application
are	O
usually	O
embedded	O
on	O
first-party	O
websites	O
and	O
collect	O
information	O
from	O
them	O
.	O
</s>
<s>
Third-party	O
cookies	B-Application
have	O
higher	O
efficiency	O
and	O
data	O
aggregation	O
ability	O
than	O
first-party	B-Application
cookies	I-Application
.	O
</s>
<s>
While	O
first-party	B-Application
cookies	I-Application
only	O
have	O
access	O
to	O
users	O
 '	O
data	O
on	O
one	O
website	O
,	O
third-party	O
cookies	B-Application
could	O
combine	O
data	O
collected	O
from	O
different	O
websites	O
to	O
make	O
the	O
image	O
of	O
the	O
user	O
more	O
complete	O
.	O
</s>
<s>
Meanwhile	O
,	O
several	O
third-party	O
cookies	B-Application
could	O
exist	O
on	O
the	O
same	O
website	O
.	O
</s>
<s>
When	O
third-party	O
cookies	B-Application
collect	O
the	O
web	B-Protocol
browsing	I-Protocol
history	I-Protocol
of	O
users	O
from	O
multiple	O
websites	O
,	O
more	O
information	O
leads	O
to	O
more	O
privacy	O
concerns	O
.	O
</s>
<s>
When	O
the	O
web	B-Protocol
browsing	I-Protocol
history	I-Protocol
from	O
these	O
two	O
websites	O
is	O
combined	O
,	O
the	O
user	O
may	O
be	O
considered	O
interested	O
in	O
news	O
related	O
to	O
medical	O
topics	O
.	O
</s>
<s>
When	O
browsing	B-Protocol
history	I-Protocol
from	O
different	O
websites	O
is	O
combined	O
,	O
it	O
could	O
reflect	O
a	O
more	O
complete	O
image	O
of	O
the	O
person	O
.	O
</s>
<s>
Although	O
no	O
user	O
IDs	O
or	O
names	O
was	O
included	O
,	O
users	O
could	O
be	O
identified	O
based	O
on	O
the	O
browsing	B-Protocol
history	I-Protocol
released	O
.	O
</s>
<s>
In	O
2020	O
,	O
Avast	O
,	O
a	O
popular	O
antivirus	O
software	O
,	O
has	O
been	O
accused	O
of	O
selling	O
browsing	B-Protocol
history	I-Protocol
to	O
third	O
parties	O
.	O
</s>
<s>
However	O
,	O
browsing	B-Protocol
history	I-Protocol
could	O
be	O
used	O
to	O
identify	O
users	O
.	O
</s>
<s>
They	O
are	O
not	O
concerned	O
about	O
being	O
tracked	B-Application
unless	O
there	O
are	O
substantial	O
impacts	O
on	O
them	O
.	O
</s>
<s>
Most	O
users	O
make	O
use	O
of	O
ad	O
blockers	O
,	O
delete	O
cookies	B-Application
,	O
and	O
avoid	O
websites	O
that	O
collect	O
personal	O
information	O
to	O
try	O
to	O
protect	O
their	O
web	B-Protocol
browsing	I-Protocol
history	I-Protocol
from	O
being	O
collected	O
.	O
</s>
<s>
There	O
are	O
a	O
series	O
of	O
open	O
source	O
projects	O
that	O
try	O
to	O
protect	O
their	O
privacy	O
through	O
collecting	O
their	O
browsing	B-Protocol
history	I-Protocol
on	O
the	O
hard	O
drive	O
instead	O
of	O
the	O
browser	B-Application
.	O
</s>
<s>
It	O
solves	O
the	O
issue	O
of	O
such	O
as	O
that	O
users	O
cannot	O
see	O
the	O
browsing	B-Protocol
history	I-Protocol
data	O
once	O
the	O
user	O
deletes	O
the	O
data	O
on	O
the	O
browser	B-Application
.	O
</s>
