A candlestick contains no information a bar chart doesn't. Same four numbers: open, high, low, close. What it adds is instant legibility — the eye reads a candle's shape faster than it reads four tick marks, which is why candlesticks conquered the world's charting software. This module teaches the anatomy once, properly, so patterns later never feel like memorization.
Anatomy: body and wicks
The body is the rectangle between open and close — the period's net result. Close above open: an up candle (typically green or white). Close below: a down candle (red or black). The thin lines above and below — wicks, or shadows — mark the high and low: territory that was visited but not held.
That last phrase is the entire skill. A long upper wick says buyers pushed price up and got rejected — someone sold everything they offered and shoved the auction back down. A long lower wick says sellers probed lower and found buyers waiting. A tall body with tiny wicks says one side controlled the period wire to wire; a tiny body with long wicks on both sides (the shape traders call a doji when the body all but vanishes) says the period ended in a stalemate after a two-way brawl. Read candles as verdicts: who tried what, and what held.
Context is most of the meaning
The famous named patterns — hammer, engulfing, shooting star and the rest, cataloged in the Library's candlestick patterns page — are just recurring wick-and-body arrangements. But the same shape means different things in different places: a long-lower-wick candle at the bottom of a decline, at a level from Module 4, on heavy volume from Module 5 is a story; the identical candle in the middle of aimless chop is noise. Steve Nison — who introduced candlestick technique to Western readers in Japanese Candlestick Charting Techniques (1991; paraphrased here) — emphasized exactly this: candle signals are read against the trend and location they appear in, never in isolation. Thomas Bulkowski's pattern statistics (his profile and the patterns page carry the details) back that up empirically — raw pattern hit-rates hover near coin-flip until context filters are added.
The origin story, told honestly
You'll hear that candlesticks were invented by Munehisa Homma, an eighteenth-century rice trader in Osaka's Dōjima market, who supposedly made a legendary fortune reading market psychology. The honest version: Homma was real, the Dōjima rice exchange was real and remarkably sophisticated, and Japanese technical traditions are genuinely old — but the specific claim that Homma drew candlestick charts as we know them is tradition, not documented history; the charts in their modern form appear much later. We tell the story because it's part of the craft's culture, and we flag it because this site doesn't launder legends into facts. What's verifiable is the modern chain: Japanese analysts kept the technique alive, and Nison's 1991 book carried it West, where it displaced bar charts within a generation.
Assignment
Pull up a daily chart and pick any ten consecutive candles. For each, write one short verdict without using any pattern names: "buyers controlled it start to finish," "sellers probed lower and were refused," "stalemate." Pattern names can come later — the fluency that matters is describing the fight from the shape alone.