Conserver is an application that allows multiple users to watch a serial
console at the same time (serial meaning 'serial data stream' here, not
necessarily any physical RS-232 port). It can log the data, allows users
to take write-access of a console (one at a time), and has a variety
of bells and whistles to accentuate that basic functionality. The idea is
that conserver will log all your serial traffic so you can go back and
review why something crashed, look at changes (if done on the console),
or tie the console logs into a monitoring system (just watch the logfile
it creates, for instance using dnotify).

Multi-user capabilities allow you to work on equipment with others, mentor,
train, etcetera. It also does all that client-server stuff so that, assuming 
you have a network connection, you can interact with any of the equipment 
from home or wherever.
