Calling through calling cards has a set procedure. Each card is assigned a number called the access number which is to be dialed first to get connected to international call zone. Thereafter he has to dial the code (011) for making international calls. This is followed by the country code, area code and the required number in the particular country.

For example if a person wants to dial a particular number in Islamabad, then the person has to first of dial his access number. With this, the service provider connects him to the long distance calling zone. Once connected, he has to dial 011+92 (country code) +51 (Area code for Islamabad) +required telephone number. With this, he is connected to the required number.

Of course memorizing all these numbers could be difficult, particularly for a person who makes frequent calls to Pakistan. Further, dialing all these numbers consumes time. In such cases he can use a utility called speed dialing. The caller will register the frequently called numbers with the helpline of the calling company. Whenever he wants to make a call, the caller will just dial the access number and the helpline will furnish the list of telephone numbers registered by the caller. The caller will choose the required number and he is instantaneously connected.

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