The Different types of Telephones are, Tellus, Bell, Rogers and Koodo those are pretty much the basic Types of Telephones but if you google search and type in Differant types of Cell phones some other places might give you a beetter offer but type in these first.
We have our key system, this one works in switching calls manually. Then the PBX system, this is a more advance system that automatically route calls to where it needs to go. The VoIP PBX on the other hand uses the hi -speed internet connection to establish calls.