Pip
A pip is the smallest standard price move in a forex quote, usually the fourth decimal place.
A pip stands for percentage in point. For most currency pairs it equals 0.0001 of the quoted price. On JPY pairs a pip is 0.01 because yen quotes carry two decimals. The value of one pip in dollars depends on lot size: at one standard lot (100,000 units) on EUR/USD, one pip equals $10. At one mini lot, $1. At one micro lot, $0.10. Pip value is what turns a 30-pip move into a measurable profit or loss.
Worked example
If EUR/USD moves from 1.0850 to 1.0853 on a one-lot trade, that is a 3-pip move worth $30. The same move on a 0.1-lot trade is worth $3.