<s>
Columbia	B-Protocol
MM	I-Protocol
(	O
Mail	O
Manager	O
)	O
is	O
a	O
computer	B-Application
program	I-Application
for	O
reading	O
email	O
using	O
a	O
command-line	B-Application
interface	I-Application
.	O
</s>
<s>
It	O
was	O
developed	O
at	O
Columbia	O
University	O
between	O
1984	O
and	O
1990	O
,	O
and	O
is	O
a	O
Unix	B-Application
reimplementation	O
of	O
a	O
1978	O
TOPS-20	B-Operating_System
email	B-Protocol
program	I-Protocol
,	O
also	O
known	O
as	O
MM	O
,	O
which	O
in	O
turn	O
was	O
an	O
update	O
of	O
an	O
earlier	O
program	O
by	O
Mike	O
McMahon	O
of	O
SRI	O
International	O
.	O
</s>
<s>
Columbia	B-Protocol
MM	I-Protocol
has	O
also	O
been	O
built	O
on	O
other	O
platforms	O
,	O
including	O
DOS	B-Device
and	O
VMS	B-Operating_System
.	O
</s>
<s>
The	O
message	O
sequence	O
feature	O
proved	O
so	O
popular	O
with	O
MM	O
users	O
that	O
TOPS-20	B-Operating_System
MM	O
author	O
Mark	O
Crispin	O
went	O
on	O
to	O
implement	O
similar	O
filtering	O
capabilities	O
in	O
Pine	B-Operating_System
.	O
</s>
<s>
Columbia	B-Protocol
MM	I-Protocol
also	O
offered	O
context-sensitive	O
help	O
,	O
command	O
completion	O
,	O
and	O
command	O
history	O
,	O
carried	O
over	O
from	O
the	O
TOPS-20	B-Operating_System
version	O
,	O
before	O
such	O
features	O
were	O
commonplace	O
in	O
Unix	B-Application
software	O
.	O
</s>
<s>
After	O
a	O
lull	O
in	O
development	O
in	O
1990	O
,	O
MM	O
development	O
picked	O
up	O
again	O
in	O
2002	O
with	O
an	O
interim	O
release	O
,	O
including	O
changes	O
for	O
Linux	O
portability	O
and	O
POP	B-Protocol
support	O
.	O
</s>
<s>
It	O
was	O
likely	O
that	O
,	O
if	O
you	O
did	O
a	O
SYSTAT	O
on	O
any	O
DEC-20	O
at	O
Columbia	O
between	O
1978	O
and	O
1988	O
,	O
you	O
would	O
see	O
about	O
half	O
the	O
users	O
running	O
EMACS	B-Application
and	O
the	O
other	O
half	O
MM	O
,	O
with	O
only	O
occasional	O
time	O
out	O
for	O
text	O
formatting	O
,	O
program	O
compilation	O
,	O
and	O
file	O
transfer	O
.	O
</s>
<s>
When	O
Columbia	O
switched	O
to	O
Unix-based	O
platforms	O
during	O
the	O
1980s	O
the	O
MM	O
program	O
was	O
rewritten	O
for	O
that	O
platform	O
and	O
development	O
continued	O
on	O
the	O
program	O
for	O
the	O
next	O
20	O
years	O
.	O
</s>
