Typically, incoming emails go
through a spam filtering service, and all clean emails are sent to the mail
server. Email routing goes a step beyond spam filtering and lets you copy or
redirect emails based on customized rules. The routing rules can be based on
the sender, recipient, or many other parameters. With email routing, an email
can be sent to the original recipient and carbon copied to additional
recipient(s), or it can be redirected to a completely different destination.