The acronym STD stands for Subscribers Trunk Dialing. These STD codes are numbers that need to be affixed before a telephone number when one dials from one Indian city to another. On the other hand if you are calling a number in India from abroad, you will first have to dial the ISD code for India followed by the STD code of the location and finally the actual number.
For example, if you are calling a number in Panaji from abroad, you
will have to dial 0091832. Here, 91 is the ISD code for India and 832 is
the STD code for Panaji. If a tour to Goa is on the cards, bring along a
list of Goa STD codes with you. Following are the STD codes for Goa