Network computer devices that originate,
route and terminate the data are called network nodes.
Nodes can include hosts such as servers as well as networking hardware.
Two such devices can be said to be networked together
when one device is able to exchange information with the other device,
whether or not they have a direct connection to each other.
System maintenance is an umbrella term that encompasses various
forms of computer maintenance needed to keep a system running.
Preventive maintenance is defined as the proactive maintenance
of equipment before a fault or failure occurs.
The goal of this form of maintenance is to restore operability to the system
by either correcting the problem or replacing the damaged components.