Now we have a look of what is a PBX or (Private branch exchange)……in a laymans term we can tell PBX is a telephone exchange in a home or in a office which can have all the features of a local telephone exchange….(it can be a hardware exchange or a software exchange)……

“A Private Branch eXchange (PBX) is a telephone exchange that serves a particular business or office, as opposed to one that a common carrier or telephone company operates for many businesses or for the general public. PBXs are also referred to as:”

• PABX – Private Automatic Branch eXchange
• EPABX – Electronic Private Automatic Branch Exchange

This is what wikipedia tells …..
as the normal telephone exchange do…we can make many extensions with a PBX can route our calls as the telephone exchange does…..for example 106 PBX means it will have 1 P&T conection and 6 extension….P&T(Post and Telegraphy) ..it is a connection that we get from our telephone exchange……and the extension means we have locally connected 6 extension phone with the PBX……..

Lets starts from the very begining….

The word PBX is some thing very nice to hear and very commenly hearing one..i heard first when i was in my degree days we had a paper there called Electronic communication…when i heard this first time did’t got anything…when i came to know the expansion of it (PBX) Private Branch exchange……i got that it was some thing related to telephone exchange….someone told me that it is like an intercom….intercom..???oops..with god grace i don’t know what is it on that time….

Later i got what really is …An intercom (intercommunication device) is an electronic communications system within a building or group of buildings….it can called as phone with in a house or an office with out a external connection…(external connection means we have a group of telephone but don’t have a connection from the telephone exchange)…and our groups of phone is interconnected…in computer terms we can call it as a Local Area telephone network or a LAN