Circuit Switching:
Many switching techniques are in use. One of them is line or circuit switching in which a communications path is actually established before the message is accepted for transmission. For voice communication circuit switching is the norm where by a path through connected circuits is established. While this method is suited to telephone traffic, it is not so, economical or efficient for data which is transmitted at different bit rates and in varying amounts.
Message Switching:
This is a different technique associated with switching. According to this method, the system accepts all messages, stores them in a computer, and transmits them as and when channels become available,