The United States Dollar: The United States Dollar (sign: $; code: USD) is the unit of currency of the United States. The U.S. dollar is normally abbreviated as the dollar sign, $, or as USD or US$ to distinguish it from other dollar-denominated currencies and from others that use the $ symbol. It is divided into 100 cents.
      The U.S. dollar is the currency most used in international transactions. Several countries use it as their official currency, and in many others it is the de facto currency.
The Pakistani Rupee: The Pakistani Rupee (sign: Rs; code: PKR) is the currency of Pakistan. The issuance of the currency is controlled by the State Bank of Pakistan, the central bank of the country. The most commonly used symbol for the rupee is Rs, used on receipts when purchasing goods and services. In Pakistan, the rupee is referred to as the "rupees", "rupaya" or "rupaye". As standard in Indian English, large values of rupees are counted in terms of thousands, lakh (100 thousand, in digits 1,00,000) and crore (10 million, in digits 1,00,00,000)
Currency Rates Converter Online: Here is a Simple Script to Convert Currency of Different Countries into Dollar or Pakistani Rupe.

Reference: http://www.onlinecurrencyconverter.net/
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