The difference between the PBX and the group telephone system is that the users of the group telephone system need manual operation to dial the external line, while the PBX automatically completes this task. The hybrid system includes the functions of the above two systems.

PBX is commonly known as SPC exchange, SPC PBX, telephone exchange, group telephone, etc. PBX is one of the commonly used means of telephone communication management in modern office, which enables telephone managers to manage external calls and internal calls collectively.