Technical Analysis, Explained

Technical analysis is the study of market behavior through the record the market itself leaves behind: prices, trading volume, and the passage of time. Instead of asking what a company is worth, it asks what market participants have actually been doing — where demand has shown up, where it has faded, and how those patterns have tended to resolve. This guide explains what the discipline is, what it isn't, and the criticisms it has to answer.

A working definition

Every trade produces a price. String those prices together and you get a chart: a compressed history of agreement and disagreement between the demand side and the supply side of a market. Technical analysis treats that history as evidence. Its core assumption is modest — not that the past repeats exactly, but that human behavior under uncertainty rhymes: fear, greed, hesitation, and capitulation leave recognizable traces in price and volume, because the people generating them respond to similar pressures in similar ways.

The technician's raw materials are deliberately few. Price says what the market decided. Volume says how much conviction stood behind the decision. Time says how long the decision took to form and how long it held. Nearly every tool in the field — from a simple moving average to a momentum oscillator — is a way of summarizing one or more of those three.

Charts as records of supply and demand

It's tempting to read a chart as a picture of a company's fortunes. More precisely, it's a record of transactions. When demand persistently exceeds supply at a given price, the price rises until balance returns. When supply overwhelms demand — holders competing to exit — the price falls. A trend is simply that imbalance sustaining over time; a reversal is the imbalance flipping.

This framing explains why technicians pay attention to levels where price stalled or turned before (see Support and Resistance) and to the pace of trading at turning points. Those are places and moments where the balance between supply and demand visibly shifted once, and markets have memory: participants who acted at a level, or regretted not acting, tend to react when price returns to it.

What technical analysis is not

It is not a valuation method. A chart cannot tell you what a business earns, what it owes, or whether its price is "fair" — questions that belong to fundamental analysis. It is not a prediction machine either; at its best it produces probabilities and scenarios, not certainties. A pattern that resolved upward most of the time in the past will still fail regularly, which is why risk management — position sizing and drawdown awareness — is part of the craft rather than an afterthought.

It also isn't self-validating. A chart pattern feels persuasive because human perception is built to find patterns, including in random noise. The honest version of the discipline therefore leans on defined rules and countable history: a setup described precisely enough to be tested, and a track record evaluated with the same skepticism you'd apply to anyone else's claims.

Within the field there are really two crafts sharing a name. Discretionary chart reading interprets each chart on its own terms — flexible, experience-driven, and hard to verify. Rule-based analysis defines its conditions in advance, applies them uniformly, and counts the results, hits and misses alike. The two overlap in vocabulary and charts, but only the second can show its work: its signals exist on specific dates at specific prices, and its claims can be checked by anyone with the data. When you evaluate any method that calls itself technical, the first question is which of the two crafts it practices.

Common criticisms, fairly stated

Technical analysis has serious critics, and their main points deserve a straight hearing.

"Prices already reflect everything." The efficient-market argument holds that public information is priced in quickly, leaving nothing exploitable in past prices. The technician's reply is that prices reflect information as participants act on it — and participants act unevenly, emotionally, and sometimes under compulsion (forced selling, index flows, margin calls). Whether that reply convinces you is a genuine open question.

"It's astrology for charts." Some chart reading is unfalsifiable storytelling — shapes named after the fact, redrawn when they fail. That criticism lands on the loose, discretionary end of the field. It lands less on rule-based approaches whose signals can be defined in advance and whose results can be counted, audited, and published — hits and misses alike.

"Backtests lie." They often do: rules tuned until they fit one historical period (overfitting), tests that quietly drop delisted failures (survivorship bias), and costs ignored. These are failures of method, not of arithmetic — and they're exactly what a careful reader checks for in any published record.

"If it worked, it would stop working." Widely copied signals can decay as crowds trade them earlier. This is a real effect and a standing argument for humility about any method's published past.

Where it fits

Used well, technical analysis is one input among several: a way to read timing, participation, and risk from the market's own behavior, combined — depending on the investor — with fundamental research, diversification, and position sizing. Used badly, it's a Rorschach test with a brokerage account attached. The difference lies in definitions written down in advance, records kept honestly, and the discipline to treat every indicator as a probability statement rather than a prophecy.

The next layer down is the trend itself — how it's defined and smoothed — in Trend and Moving Averages, and the indicator survey in Popular Technical Indicators.

Educational material only — not investment advice.