RR or RR - from English Risk-Reward. The ratio of risk to profit. Represented as 1 to 2/1 to 3/1 to 10/1 to 0.5, etc. Where 1 is the risk; 2/3/10 is the profit, meaning how many times the profit exceeds the initial risk. For example: when the stop loss triggers, the loss = $100, when the take profit triggers, the profit = $300 - this is a trade with RR = 1 to 3. Since all traders have different deposits and different risks in $, this parameter is used to describe trade efficiency. Trades with an RR of 1 to 3 and above are considered the "gold standard" as they allow for long-term profitable trading even with a win rate of 30-40%, as successful trades cover several losing ones immediately.
R or R - "one Risk". This is a unit of measurement for trade efficiency, derived from the definition of RR above. It allows for the calculation of profit/loss in a trade and for exchanging these values without specifying the exact size of positions and cost in $. For example: "the price reacted +4R, we take 50% and take 2R" - means that the price gave a profit = 4 times the Risk (loss on stop = $100, i.e. 1R = $100, the trade gave a profit of $400 or 4R, we fix 50% = 2R = $200).
Win rate - the share of successful/profitable trades from the total number of trades. For example, a win rate of 60% means that out of 10 trades, 6 were profitable and only 4 were losses.