<s>
POPmail	B-Operating_System
was	O
an	O
early	O
e-mail	O
client	O
written	O
at	O
the	O
University	O
of	O
Minnesota	O
.	O
</s>
<s>
The	O
original	O
version	O
was	O
a	O
Hypercard	B-Application
stack	I-Application
that	O
acted	O
as	O
a	O
Post	B-Protocol
Office	I-Protocol
Protocol	I-Protocol
client	O
.	O
</s>
<s>
Later	O
versions	O
of	O
POPmail	B-Operating_System
were	O
written	O
as	O
normal	O
Macintosh	O
applications	O
,	O
and	O
a	O
PC	O
version	O
of	O
POPmail	B-Operating_System
was	O
also	O
released	O
.	O
</s>
<s>
POPmail	B-Operating_System
and	O
Eudora	B-Operating_System
were	O
both	O
instrumental	O
in	O
moving	O
higher	O
education	O
e-mail	O
use	O
away	O
from	O
terminal-based	O
user	O
interfaces	O
and	O
into	O
a	O
client	O
–	O
server	O
GUI	O
metaphor	O
.	O
</s>
