(Percentage in Points): This is the smallest change in price for any currency pair. Except for the Japanese Yen and a few other currencies. The pairs are mostly shown with 5 decimal places. The 4th decimal point in a price quote is called a ‘pip’, while the 5th is referred to as a ‘nano pip’.
If the GBP/USD pair for example changes from 1.4558 to 1.4559, the difference is (1.4559-1.4558) =0.0001. The price would be said to have increased by 1 pips.