Money and returns
Profit per unit — what you keep on one item after every cost.
Profit per hour — what a building earns while it runs. The number that matters most.
Margin — profit as a percentage of the sale price. A measure of cushion, not of quality.
Break-even price — the sale price at which profit is exactly zero.
ROI — return on investment: what you got back as a percentage of what you put in.
Payback period — how long an investment takes to earn back its cost.
Opportunity cost — the profit you gave up by choosing this over the best alternative.
Working capital — money tied up in stock and running costs rather than available to spend.
Production
Input / material — something consumed to make something else.
Output — what a production line produces.
Recipe — the set of inputs and quantities needed for one unit of output.
Throughput — units produced or sold per hour.
Administration overhead — a percentage that multiplies your wage bill, rising with company size.
Vertical integration — producing your own inputs instead of buying them.
Bottleneck — the step in a chain that limits everything downstream.
Markets
Order book — all the open offers for a product.
Depth — how many units are available near the current price.
Liquidity — how easily you can buy or sell without moving the price. We score it 0–100 from depth and the number of sellers.
Volatility — how much a price moves about, as a percentage, so different price levels compare directly.
Spread — the gap between the cheapest and dearest current offers.
Quality — a product’s grade. An offer satisfies any requirement at or below its quality.