Trading stocks requires deep understanding: supply and demand are what determine the fate of prices

Many investors wonder why stock prices go up and down. Sometimes they rise without apparent reason, and sometimes they fall sharply. In reality, all of this is driven by a single force: supply and demand that operate behind the scenes of various price figures. In this article, we will delve into how these two forces work and, most importantly, how you can use them to make investment decisions.

Before talking about trading, understand supply and demand first

Basic economics tells us that there are two opposing forces in the market: buy side and sell side.

Demand refers to the number of people wanting to buy at different prices. In practice, if the price drops, more people want to buy (because it’s cheaper). If the price rises, fewer people want to buy (because it’s more expensive). This is called the “law of demand.”

Supply is the opposite — the number of people wanting to sell. When prices are high, sellers are willing to sell; when prices are low, sellers are less eager to sell. This is the “law of supply.”

When both forces meet, an equilibrium (is reached) occurs — the price level where there are no excess buyers or sellers. This is the “fair” price accepted by the market.

In the stock market, supply and demand look like this

When good news (such as a company’s profits soaring) occurs, investors believe that prices will rise — demand increases. Sellers see the price improving and want to hold on, expecting further gains. The market reaches a new equilibrium, and prices float higher.

Conversely, bad news (such as a company losing) hits the market, and investors want to sell — supply surges. Buyers want to exit, and the equilibrium shifts downward, causing prices to plummet.

But not only news affects supply and demand; many other factors do as well:

On the demand side:

• Low interest rates (= seek higher returns in stocks)
• Abundant liquidity (= more money flowing into stocks)
• Investor confidence (= optimism = desire to buy)
• Economic outlook forecasts

On the supply side:

• Company policies (= share buybacks = reduce supply)
• New companies entering the market via IPOs
• Tax policies and regulations

All numbers matter: viewing supply and demand through technical analysis

Skilled traders don’t just listen to news; they read price charts to identify where buying and selling pressures are.

1) Candlestick charts (Candlestick) reveal the truth

• Green = close higher than open = buying pressure wins = strong demand
• Red = close lower than open = selling pressure wins = strong supply
• Doji = open equals close = indecision between buyers and sellers = unclear

2) Trends (Trend) are about momentum

• If prices make new highs consistently = demand remains strong = continue upward
• If prices make new lows consistently = supply remains strong = continue downward
• If prices fluctuate sideways = no clear winner = wait for a breakout

3) Support & Resistance (Support & Resistance) = points where supply and demand collide

• Support = price level where buyers are waiting = “where to buy” = high demand
• Resistance = price level where sellers are waiting = “too expensive” = high supply

Supply and demand have two main trading methods

The Demand Supply Zone technique is an effective way to time entries and exits. When prices move (up or down) and then consolidate, the original trend often resumes, as if the same forces are pushing back.

Method 1: Trading Reversal Points (Reversal)

After a rally (and consolidation), if selling pressure returns strongly, the price may reverse downward:

• Break below the support of the consolidation = sell signal
• Place a Stop Loss above the entry point
• Target the next support level below

Similarly, after a drop (and consolidation), if buying pressure returns, the price may bounce back up:

• Break above the resistance of the consolidation = buy signal

Method 2: Trading with the trend (Continuation)

More often than reversals, after consolidation, prices tend to resume the original trend:

• Price rises → consolidates → breaks resistance → continues upward
• Price drops → consolidates → breaks support → continues downward

Its power lies in statistics: trends show signals until they change.

Summary: Why supply and demand are crucial for investing

Supply and demand are not just economic terms — they are the language the market speaks every day, every minute. Both long-term investors and day traders rely on this principle equally.

Good news creates demand → prices go up
Bad news creates supply → prices go down
No news — supply and demand balance out → prices fluctuate

By learning to read these forces well, you can understand what the market is thinking now and what it might do next. That’s the first step toward becoming a savvy investor.