Question & Answer
QUESTION

Full form of STD,ISD and PCO.where are these used ?

ANSWER

Subscriber trunk dialling-STDĀ 

International Subscriber Dialling-ISDĀ 

PublicCall Office-PCO

This is used in a telephone system allowing subscribers to dial trunk calls without operator assistance through trunk lines .


"Have a doubt going on your head? Download Vedantu's Instant Doubt Solving App now and get all your doubts cleared by our experts."