The
telecommunication system is primarily based upon the 'Fragment Calling
System' that is predominantly used in the member nations of European
Union. This system works in fragment i.e. each location is prescribed a
certain code that is popularly called STD code. This code is clubbed
with the ISD code of that particular country which in turn is clubbed
with the phone number one wants to call. For example if you want to call
a number say 26xxxxx in the city of Noida in Uttar Pradesh, from London
then you would first dial +91 i.e. the ISD code of India followed by
120, the STD code of Noida and then 26xxxxx. Here is the list of STD
codes of the cities in Utter Pradesh: -
