What actually moves the market?

At its core, the stock market is driven by one simple force: supply and demand. This law shows up everywhere in the economy. Whether we’re talking about houses, oil, trainers, or the one kid at school selling sweets in the playground, the same rule applies.

If more people want to buy something than sell it, the price goes up.
 If more people want to sell something than buy it, the price goes down.

The stock market works in exactly the same way. Every second of the trading day, there are buyers and sellers placing orders. When buyers outnumber sellers, prices rise. When sellers outnumber buyers, prices fall.

Simple in theory.

In practice, the question becomes: why do people suddenly want to buy or sell a stock? That’s where things get more interesting. Broadly speaking, there are three main forces that drive the stock market:

• Company fundamentals
• The economy
• Investor sentiment And all three ultimately feed into that same supply-and-demand machine.

1. Company fundamentals Let’s start with the most direct driver: company fundamentals. This simply refers to the actual performance of a business. Things like:

• Revenue (how much money the company brings in)
• Profit (how much it keeps)
• Growth
• Investments
• Acquisitions
• Debt levels
• Future guidance

Public companies are required to report their financial results every quarter, which means investors regularly get new information about how a business is performing. When a company releases earnings, investors immediately compare the results to expectations. If a company reports better-than-expected earnings, investors may rush to buy the stock. Demand increases, supply stays the same, and the price rises. If earnings miss expectations, investors may sell. Supply increases, demand falls, and the price drops. The key point here is that fundamentals affect how attractive a company looks to investors, which directly influences buying and selling decisions. But companies don’t exist in isolation. They operate inside a much bigger system: the global economy.

2. The Economy If company fundamentals are the engine of a stock, the economy is the road it’s driving on. And right now, that road sometimes feels like the Wild West. Over the past few years alone, we’ve seen events that have shaken markets across the world:

• The COVID-19 pandemic
• The Russia–Ukraine war
• Global inflation spikes
• Rising interest rates
• Trade tensions and tariffs
• Conflicts in the Middle East

Each of these events changes how investors think about the future. Take COVID-19 as an example. When travel stopped almost overnight, airlines, hotels, and cruise companies saw demand collapse. Investors expected profits to fall sharply, so many rushed to sell airline stocks. More sellers than buyers means one thing: prices drop. Or consider oil markets during geopolitical conflict. If investors believe oil supply might be disrupted, they expect prices to rise. That expectation alone can trigger buying in energy stocks. Again, supply and demand in action. Economic forces shape the environment in which businesses operate. When the environment changes, investor behaviour changes too. And that leads us to the final and arguably most powerful driver.

3. Sentiment If fundamentals and economics are the rational side of the market, sentiment is the emotional side. Sentiment is simply how investors feel. You can call it:

• mood
• confidence
• fear
• greed

It all means roughly the same thing. If investors feel optimistic about the future, they tend to buy more stocks. Demand rises and prices go up. If investors feel nervous or uncertain, they may sell first and ask questions later. Supply increases and prices fall. What makes sentiment so powerful is that it can move markets even when nothing has fundamentally changed. A rumour, a headline, or a sudden shift in perception can trigger waves of buying or selling. And because markets are made up of millions of human decisions, sentiment can spread quickly. One investor sells.
Then another.
Then another. Before you know it, prices are moving fast.

Understanding sentiment is less about spreadsheets and more about human psychology and risk tolerance.

One of the most famous quotes in investing comes from Benjamin Graham, often called the father of value investing. He said: “In the short run, the market is a voting machine, but in the long run it is a weighing machine.”

What he meant is this: In the short term, markets behave like a popularity contest. News, emotion, and investor opinion push prices up and down every day. But over the long term, what really matters is the underlying weight of a business, its profits, assets, and ability to generate value. Eventually, strong companies tend to see their stock prices reflect that strength.

So when you see a stock move, it usually comes back to one of these three forces: Company fundamentals – how the business is actually performing.
 The economy – the wider environment in which companies operate.
 Sentiment – how investors feel about the future.

All three ultimately feed into the same mechanism: Supply and demand.

More buyers than sellers? The price rises.
 More sellers than buyers? The price falls.

The stock market may sometimes feel chaotic, unpredictable, or even a bit like the Wild West. But underneath all the noise, the same basic forces are always at work.