For some telephone exchanges, a strictly defined classification cannot be unified. Due to the different names of manufacturers, customs, regions, product positioning and other factors. So you don't need to pursue it too deliberately, just purchase the appropriate equipment according to your own use requirements.

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.