<s>
CSS	B-General_Concept
image	I-General_Concept
replacement	I-General_Concept
is	O
a	O
Web	O
design	O
technique	O
that	O
uses	O
Cascading	B-Language
Style	I-Language
Sheets	I-Language
to	O
replace	O
text	O
on	O
a	O
Web	O
page	O
with	O
an	O
image	O
containing	O
that	O
text	O
.	O
</s>
<s>
It	O
is	O
intended	O
to	O
keep	O
the	O
page	O
accessible	O
to	O
users	O
of	O
screen	O
readers	O
,	O
text-only	O
web	B-Application
browsers	I-Application
,	O
or	O
other	O
browsers	B-Application
where	O
support	O
for	O
images	O
or	O
style	O
sheets	O
is	O
either	O
disabled	O
or	O
nonexistent	O
,	O
while	O
allowing	O
the	O
image	O
to	O
differ	O
between	O
styles	O
.	O
</s>
<s>
Also	O
named	O
Fahrner	B-General_Concept
image	I-General_Concept
replacement	I-General_Concept
for	O
Todd	O
Fahrner	O
,	O
one	O
of	O
the	O
persons	O
originally	O
credited	O
with	O
the	O
idea	O
of	O
image	O
replacement	O
in	O
2003	O
.	O
</s>
<s>
The	O
typical	O
method	O
of	O
inserting	O
an	O
image	O
in	O
an	O
HTML	B-Language
document	O
is	O
via	O
the	O
<img>	O
tag	O
.	O
</s>
<s>
While	O
the	O
alt	O
attribute	O
is	O
designed	O
for	O
providing	O
a	O
textual	O
representation	O
of	O
the	O
image	O
content	O
,	O
this	O
precludes	O
the	O
use	O
of	O
HTML	B-Language
markup	O
in	O
the	O
textual	O
representation	O
and	O
causes	O
problems	O
with	O
some	O
search	O
robots	O
.	O
</s>
<s>
Using	O
the	O
<img>	O
tag	O
to	O
show	O
text	O
is	O
presentational	O
;	O
many	O
Web	O
designers	O
argue	O
that	O
presentational	O
elements	O
should	O
be	O
separated	O
from	O
HTML	B-Language
content	O
by	O
placing	O
the	O
former	O
in	O
a	O
CSS	B-Language
style	I-Language
sheet	O
.	O
</s>
<s>
Images	O
referenced	O
using	O
an	O
<img>	O
tag	O
cannot	O
be	O
easily	O
changed	O
via	O
CSS	B-Language
,	O
causing	O
problems	O
with	O
alternative	O
stylesheets	O
.	O
</s>
<s>
Fahrner	B-General_Concept
image	I-General_Concept
replacement	I-General_Concept
was	O
devised	O
to	O
rectify	O
these	O
issues	O
.	O
</s>
<s>
Through	O
style	O
sheets	O
,	O
the	O
heading	O
was	O
then	O
given	O
a	O
background	O
containing	O
the	O
desired	O
image	O
,	O
and	O
the	O
<span>	O
hidden	O
by	O
setting	O
its	O
display	O
CSS	B-Language
property	O
to	O
none	O
:	O
</s>
<s>
The	O
Phark	O
method	O
had	O
its	O
own	O
problems	O
,	O
however	O
;	O
in	O
visual	O
browsers	B-Application
where	O
CSS	B-Language
was	O
on	O
but	O
images	O
off	O
,	O
nothing	O
would	O
display	O
.	O
</s>
