Lot
The unit of position size on forex. A standard lot is usually 100,000 units of the base currency; mini and micro lots are fractions of it.
Definition
A lot is the unit of position size on forex: a standard lot is usually 100,000 units of the base currency, while mini (0.1) and micro (0.01) lots are fractions of it. You choose the lot size from your monetary risk and the distance to your stop-loss — not “by eye” because you like round numbers.
Example
On EUR/USD, with a 20-pip stop and 100 PLN of risk, you work out the pip value for a micro lot and choose the volume so that 20 pips is roughly 100 PLN (plus a buffer for spread and slippage). That is how the lot connects to the 1–2% rule.
Anti-example / common mistake
“Always 0.1 lot” regardless of the stop and the account size. With a wide stop that is hidden oversizing; with a narrow stop it is undersizing or randomness relative to the risk plan.