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A–Z

A B C D E F G H I K L M O P R S T V W

A

• Anchoring — Getting stuck on the first number you saw.
• ATR (Average True Range) — The average size of a bar's full range, used to measure volatility.

B

• Backtest — Testing a trading rule on old price data to see what would have happened.
• Bid, ask and spread — The bid is what buyers offer, the ask is what sellers want. The gap between them is the spread.
• Bitcoin and crypto — From a 2008 white paper to EU rules.
• Bollinger Bands — A moving average with a band above and below it, based on volatility.
• Bubbles and crashes — From the South Sea Bubble to the 2010 Flash Crash.

C

• Candlestick — A chart bar that shows the open, high, low and close of a time period.
• CFDs (contracts for difference) — A leveraged bet on a price change, without owning the underlying asset.
• Commodities — Raw materials like oil, gold, wheat and natural gas.
• Confirmation bias on charts — Seeing what you already believe in a chart.
• Contango and backwardation — Whether later futures contracts cost more (contango) or less (backwardation) than nearby ones.
• Correlation — How much two markets tend to move together.
• Crypto-assets — Digital tokens like bitcoin, traded on crypto platforms around the clock.
• Cup and handle — A rounded dip (the cup) followed by a small dip (the handle).

D

• Day order and GTC — How long your order stays alive: until the end of the day, or until you cancel it.
• Discipline and if-then plans — Deciding in advance what you will do when X happens.
• Disposition effect — Selling winners too early and holding losers too long.
• Do chart patterns work? What the research says — Short version: the evidence is mixed, and patterns are hard to define objectively.
• Doji — A candle where the open and close are (almost) the same, so the body is a thin line.
• Double top and double bottom — Two peaks (or dips) at about the same level, said to signal a turn.
• Drawdown — How far your account falls from its highest point before it recovers.

E

• Economic news releases (CPI, jobs, Fed) — Scheduled economic numbers that can move markets in seconds.
• Engulfing pattern — Two candles where the second body completely covers the first one.
• Expectancy — The average amount you win or lose per trade over many trades.

F

• Fees and commission — What you pay to trade: commissions, spreads, funding and other costs.
• Flags and pennants — A short pause after a sharp move, shaped like a small flag or triangle.
• FOMO and attention-grabbing stocks — Buying what everyone is talking about.
• Forex (currencies) — Trading one currency against another, like euros against dollars.
• From gold to floating currencies — How money lost its link to gold.
• Funding rate — A regular payment between buyers and sellers of perpetual crypto futures that keeps the price close to the spot price.
• Futures — A contract to buy or sell something at a set price on a future date.

G

• Gambler's fallacy — Thinking a win is 'due' after a string of losses.
• Gaps — A jump in price where nothing traded in between, visible as an empty space on the chart.

H

• Hammer — A candle with a small body at the top and a long lower wick.
• Head and shoulders — Three peaks with the middle one highest, said to signal a turn from up to down.
• Hindsight bias — 'I knew it all along' after the fact.
• House-money and break-even effects — After wins people take more risk; after losses they chase a break-even.
• How do retail traders actually do? — What regulators and researchers measured, figure by figure.
• How to read a candlestick chart — Body, wicks, colours and timeframes, step by step.
• How to test a trading claim — Turn a guru's sentence into a fair test with costs.

I

• Illusion of control — Feeling more in control of chance than you are.
• In-sample vs out-of-sample — Practice data versus fresh data the rule has never seen.

K

• Kelly criterion — A formula for the bet size that grows money fastest in theory, if you know your true odds.

L

• Leverage — Trading with borrowed money, so a small deposit controls a bigger position. Gains and losses both get bigger.
• Limit order — Buy or sell only at your price or better.
• Liquidity — How easily you can buy or sell something quickly without moving its price much.
• Long and short — Long = you profit if the price rises. Short = you profit if the price falls.
• Look-ahead bias — Using information in a test that you could not have known at that moment.
• Loss aversion — Losing hurts more than winning feels good, so people treat gains and losses differently.
• Lot — A standard bundle size for a trade, common in forex.

M

• MACD — The gap between a fast and a slow moving average, plus a signal line.
• Margin — The money you must put up to open and keep a leveraged position.
• Margin call — A demand from your broker to add money because your account fell too low.
• Market hours and sessions — When markets are open, and why it matters.
• Market maker — A firm that keeps posting buy and sell prices, earning from the spread.
• Market order — Buy or sell right now at the best available price.
• Moving averages — The average price over the last N bars, drawn as a smooth line.

O

• OCO order (one cancels the other) — Two linked orders: when one fills, the other is cancelled.
• Options — A contract that gives the right, but not the duty, to buy or sell at a set price.
• Order book — The live list of all waiting buy and sell orders at each price.
• Overfitting — When a trading rule fits old data so tightly that it only learned the noise.
• Overtrading — Trading more than your plan says, often to chase losses or excitement.

P

• P-hacking and data snooping — Trying many tests until one looks good by luck, then only showing that one.
• Paper money and bills — From Chinese notes to European bills of exchange and banknotes.
• Paper trading and demo accounts — Practising with fake money before using real money.
• Pip — A tiny standard step in a currency price, used to count forex moves.
• Position sizing — Picking how big a trade is, based on how much you are willing to lose.

R

• R-multiple — A trade result measured in units of the amount you risked (R).
• Random entry (random twin) — A fake trade that enters at a random moment, used as a fair comparison.
• Recency bias and extrapolation — Expecting the recent past to keep going.
• Red flags in trading promotions — Warning signs regulators list for trading 'opportunities' online.
• Revenge trading (after a loss) — Taking extra risk to win back a loss quickly.
• Rice, grain and the birth of futures — From the Dojima rice market to Chicago and screen trading.
• Risk of ruin — The chance that losses shrink your account so far you can't continue.
• Risk per trade — The share of your account you are willing to lose on one trade.
• Risk-reward ratio — How much you might lose compared with how much you hope to win on a trade.
• RSI (Relative Strength Index) — A 0–100 score of how strong recent up-moves were compared with down-moves.

S

• Sample size — How many trades or data points a result is based on.
• Shells and the first coins — How people paid before and after the coin.
• Short selling — Selling something you don't own yet, hoping to buy it back cheaper later.
• Slippage — The gap between the price you wanted and the price you actually got.
• Start here: trading in 10 minutes — The basics in plain language, plus where to go next.
• Stock indices — A single number that tracks a basket of stocks, like the S&P 500.
• Stocks (shares) — A small piece of ownership in a company, traded on an exchange.
• Stop order — An order that becomes a market order once a set price is reached.
• Stop-limit order — A stop that turns into a limit order instead of a market order.
• Stop-loss — A stop order used to cap the loss on an open trade.
• Stress, emotions and the body — Trading moves your body chemistry, even for professionals.
• Support and resistance — Price areas where traders say the price often stopped falling (support) or rising (resistance) before.
• Survivorship bias — Only looking at the winners that are still around, and forgetting the ones that disappeared.

T

• Take-profit order — A limit order that closes your trade when it reaches a profit target.
• The first shares and exchanges — How share trading started in the 1600s.
• Timeframe — The time each bar or candle on a chart covers, like 1 minute, 1 hour or 1 day.
• Trading costs — What you pay to get in and out of a trade, and why a tight stop leaves costs a bigger bite of your risk.
• Trading journal — Writing down each trade, why you took it and how you felt.
• Trailing stop — A stop that follows the price as it moves your way.
• Trend — The general direction a price has been moving: up, down or sideways.
• Triangles — Price swings that get smaller and squeeze into a triangle shape.
• Tulip mania: fact and fable — The 1637 tulip price collapse, and why the famous story is mostly wrong.

V

• Volatility — How much and how fast a price moves up and down.
• Volume — How much of something traded in a period.
• VWAP — The average price of the day, weighted by how much traded at each price.

W

• Wedges — Two sloping lines that point the same way and come together.
• Win rate — The share of trades that end with a profit.

Short definitions of more words: glossary.

Education only, not financial advice. No signals. Backtests are hypothetical: real trading can be worse. Past results don't predict future results.