face to faceThis channel is a chann

face to face
This channel is a channel that can best be seen in the behavior of a person and can respond instantly makes the work fast and more efficiently.
telelphone
This communication can be heard and can reply immediately, but can not see the facial expression of the opponent, so The caller must be communicated to the opposing understand the purpose to avoid errors in their work.
E-mail
The electronic letter .You need to check to know that who sent an email to you. Currently, the most widely used
litter
The letter opponent, which need time to make a delayed implementation within the organization.
formal report
is a Writing formal reports and no response