How Stock Markets Work: A Beginner's Guide to Buying and Selling Shares
Learn how stock markets work from the ground up. Understand stock exchanges, buyers and sellers, orders, bid and ask prices, price discovery, NIFTY, SENSEX, settlement and the journey of a stock-market transaction.
What Is a Stock Market?
A stock market is a marketplace where shares and other securities can be bought and sold.
When investors buy shares of a listed company, they participate in a market where buyers and sellers come together to determine prices through orders and transactions.
The simplest way to think about it is:
The stock market connects buyers and sellers of securities.
Modern stock markets are not simply physical locations. Trading is conducted through electronic systems involving exchanges, brokers, clearing corporations, depositories and other market infrastructure.
In India, investors commonly access the market through brokers and exchanges such as NSE and BSE.
Why Do Stock Markets Exist?
Stock markets perform an important economic function.
They help companies access capital and provide investors with a marketplace where securities can be bought and sold.
This creates two connected markets: the primary market and the secondary market.
The primary market helps companies and other issuers raise capital.
The secondary market allows investors to trade securities that have already been issued.
An active secondary market is important because investors are generally more willing to provide capital when they know there is a mechanism through which they can later sell their holdings.
Primary Market vs Secondary Market
Primary Market
In the primary market, new securities are issued to investors.
An Initial Public Offering, or IPO, is one example.
Suppose a company wants to raise capital by offering shares to the public. Investors participate in the offering according to its terms, and the company can raise capital through the issue.
Secondary Market
After shares are listed, investors can buy and sell them among themselves.
Suppose Investor A owns shares and wants to sell them while Investor B wants to buy them.
A transaction can occur when compatible orders are matched according to market rules.
The money in a normal secondary-market transaction generally moves between the buyer and seller rather than directly to the company.
What Is a Stock Exchange?
A stock exchange provides the infrastructure and rules that facilitate trading in listed securities.
In India, NSE and BSE are major stock exchanges.
An exchange provides systems through which eligible securities can be traded according to its rules and procedures.
It is therefore more than a website showing prices. Exchange infrastructure is part of a broader system involving trading, clearing, settlement, surveillance and regulation.
NSE and BSE
NSE and BSE are important parts of India's securities market.
They provide electronic marketplaces where eligible securities can be traded according to their respective rules and systems.
Investors normally do not send orders directly to an exchange themselves.
Instead, they use a registered broker or trading platform.
The broker receives the investor's order and routes it through the relevant market infrastructure.
What Happens When You Buy a Stock?
Let's follow a simple example.
Suppose you want to buy 100 shares of a company.
You open your trading platform and enter an order.
The order contains information such as:
Your broker receives the order and sends it into the relevant market system.
The order can then be matched against compatible sell orders according to the exchange's matching rules.
If a compatible seller is available, a trade can occur.
The transaction is subsequently processed through clearing and settlement.
This process is electronic and can occur very quickly.
Who Is the Seller When You Buy a Stock?
When you buy an already-listed share in the secondary market, another market participant is generally selling it.
That seller could be:
The company itself does not normally receive money every time one investor buys shares from another investor in the secondary market.
The transaction represents a transfer of ownership between market participants.
What Are Buyers and Sellers?
Every completed transaction requires both sides.
A buyer wants to purchase shares.
A seller wants to sell shares.
Their interaction contributes to the market price.
If buyers become more aggressive and are willing to pay higher prices, upward price pressure can develop.
If sellers become more aggressive and buyers are willing to transact only at lower prices, downward price pressure can develop.
This continuous interaction is part of price discovery.
What Is Price Discovery?
Price discovery is the process through which market participants determine the price at which securities trade.
Investors continuously evaluate information and expectations such as:
Participants then submit orders based on their expectations.
The resulting transactions contribute to the market price.
This is why a stock can change price even when the company's physical business has not changed that day.
Expectations about the future can change much faster than the business itself.
What Is a Bid Price?
The bid price is the price at which a buyer is currently willing to buy a security, according to the available orders.
For example:
Bid: ₹500
This means a buyer is willing to purchase at ₹500, subject to the quantity and market conditions represented by the order.
What Is an Ask Price?
The ask price, also called the offer price, is the price at which a seller is currently willing to sell.
Suppose the market shows:
Bid: ₹500
Ask: ₹501
The difference between the two is the bid-ask spread.
What Is the Bid-Ask Spread?
The bid-ask spread is the difference between the highest available bid and the lowest available ask.
In the example above:
₹501 − ₹500 = ₹1
A narrow spread generally means buyers and sellers are relatively close in their willingness to transact.
A wider spread can increase transaction costs, particularly in less liquid securities.
Liquidity is therefore important when trading individual stocks.
Market Orders and Limit Orders
Two basic order types beginners should understand are market orders and limit orders.
Market Order
A market order instructs the broker to buy or sell at the available market prices.
The priority is generally execution rather than a specific price.
The final execution price can differ from the price visible on the screen, particularly in a fast-moving or less liquid market.
Limit Order
A limit order specifies the maximum price a buyer is willing to pay or the minimum price a seller is willing to accept.
For example, an investor may place a buy limit order at ₹500.
The order can execute only at ₹500 or better according to applicable market rules.
The trade-off is that execution is not guaranteed.
What Is a Trading Account?
A trading account is used to place buy and sell orders for securities through a broker.
The trading account connects the investor to the market infrastructure.
An investor uses a trading platform to enter orders, monitor positions and manage transactions.
What Is a Demat Account?
A Demat account is used to hold securities in electronic form.
When an investor buys shares and settlement is completed, the securities are held electronically rather than as physical certificates.
In India, investors commonly use a combination of:
Bank account + Trading account + Demat account
The bank account provides funds, the trading account facilitates transactions and the Demat account holds securities electronically.
Exact arrangements can vary by broker and financial institution.
What Is Clearing and Settlement?
A trade is not simply complete because an order has matched.
The market also needs to complete clearing and settlement.
Clearing determines the obligations arising from trades, while settlement is the process through which securities and funds are transferred according to the applicable market rules and settlement cycle.
Settlement cycles and procedures can change, so investors should verify the current rules applicable to their market.
Why Do Stock Prices Move?
Stock prices move because expectations and buying and selling activity change.
Imagine a company announces earnings that are significantly better than investors expected.
Buyers may become more aggressive, increasing demand for the shares.
The stock price may rise.
Now imagine the company reports weak earnings or warns that future profits could decline.
Investors may reduce their willingness to hold the stock.
More selling pressure can push the price lower.
The key idea is:
Stock prices reflect changing expectations about future value.
What Causes Market-Wide Moves?
Individual stocks can move because of company-specific news.
Entire markets can also move because of broader factors.
Examples include:
This is why a stock can fall even when its own business has not released negative news.
A broad market decline can affect many securities simultaneously.
What Are NIFTY and SENSEX?
NIFTY and SENSEX are market indices.
They are not individual stocks.
An index tracks a selected group of securities according to its methodology and provides a way to observe the performance of a particular segment of the market.
NIFTY and SENSEX are widely followed indicators of the Indian equity market.
If NIFTY rises, it does not mean every stock in India has risen.
Similarly, if SENSEX falls, some individual companies can still increase in value.
An index provides a broader market perspective.
How Does an Index Differ From a Stock?
A stock represents ownership in an individual company.
An index represents a selected group of securities according to a defined methodology.
In simple terms:
Stock: One listed company.
Index: A selected group of companies represented through an index calculation.
This distinction is important when comparing individual stock performance with broader market performance.
What Is Trading Volume?
Trading volume refers to the number of shares traded during a particular period.
High volume can indicate substantial market participation.
Low volume can indicate less trading activity.
Volume is often studied alongside price to understand market behaviour.
For example, a strong price move accompanied by unusually high volume may attract more attention than a similar move on very low volume.
However, volume alone does not tell you whether a stock is a good investment.
What Is a Bull Market?
A bull market generally refers to a sustained period of rising market prices and positive investor sentiment.
During a bull market, investors may have stronger expectations about economic growth, corporate earnings and future returns.
Bull markets can still contain corrections and temporary declines.
A rising market does not move upward every day.
What Is a Bear Market?
A bear market generally refers to a prolonged period of declining prices and negative sentiment.
During a bear market, investors may become more concerned about economic growth, corporate earnings, valuations or other risks.
Bear markets can involve substantial volatility and uncertainty.
Investing vs Trading
The stock market supports both investing and trading, but the two approaches are different.
Investing
Investing generally focuses on the underlying business and a longer time horizon.
An investor may buy shares because they believe the company can grow earnings and cash flows over several years.
Trading
Trading generally focuses more heavily on shorter-term price movements and market opportunities.
A trader may hold a position for minutes, days or weeks depending on the strategy.
Neither approach is automatically superior.
The key is having a clearly defined objective, risk-management process and time horizon.
Why Stock Markets Matter to the Economy
Stock markets help businesses access capital.
They allow investors to participate in business growth.
They provide a mechanism for price discovery.
They allow investors to transfer ownership through secondary-market transactions.
They also provide information about how market participants view the future prospects and risks of companies and the economy.
A functioning capital market can therefore support business investment and economic development.
Common Beginner Mistakes
New investors and traders often make mistakes because the stock market can appear simpler than it actually is.
Common mistakes include:
Learning how the market works can help beginners avoid many of these mistakes.
A Simple Example of a Stock-Market Transaction
Suppose Company ABC is trading at ₹500.
An investor wants to buy 100 shares.
The investor enters a limit order to buy 100 shares at ₹500.
Another market participant has a compatible sell order at ₹500 for 100 shares.
The orders match.
The transaction value is:
100 × ₹500 = ₹50,000
The transaction then moves through the applicable clearing and settlement process.
After settlement, the buyer receives the shares electronically and the seller receives the corresponding funds according to the market's procedures.
This simple example represents the basic economic function of the secondary market.
What Beginners Should Learn Next
Once you understand how the stock market works, the next logical topics include:
Understanding market infrastructure first makes these later concepts easier to place in context.
Final Thoughts
The stock market is essentially a system that allows capital and ownership to move between businesses and investors.
Companies can raise capital through the primary market.
Investors can trade existing securities through the secondary market.
Exchanges provide the marketplace and trading infrastructure.
Brokers connect investors to that infrastructure.
Buyers and sellers submit orders.
Orders interact according to market rules.
Trades are cleared and settled.
Prices continuously change as market participants update their expectations about companies, industries and the economy.
Once you understand this basic process, the stock market becomes much less mysterious.
The next step is not to start trading immediately.
It is to understand what you are buying, how the business creates value, how the market values it and what risks you are accepting.
That is the foundation of disciplined equity investing.
Frequently Asked Questions About Stock Markets
How does the stock market work?
The stock market allows buyers and sellers to trade securities. Investors place orders through brokers, and compatible orders can be matched through exchange trading systems. Completed trades then go through clearing and settlement.
What is a stock exchange?
A stock exchange provides the marketplace, systems and rules through which eligible securities can be traded.
What is the difference between NSE and BSE?
NSE and BSE are major Indian stock exchanges that provide electronic marketplaces for trading eligible securities. Each operates under its own rules, systems and listed products.
What is the difference between a stock market and a stock exchange?
A stock market refers broadly to the marketplace and ecosystem in which securities are bought and sold. A stock exchange is a specific organized marketplace and infrastructure provider within that ecosystem.
What is price discovery?
Price discovery is the process through which buying and selling activity and market participants' expectations contribute to determining the price at which securities trade.
What is a bid price?
The bid is the price at which a buyer is willing to purchase a security, according to the available order.
What is an ask price?
The ask is the price at which a seller is willing to sell a security, according to the available order.
What is the bid-ask spread?
The bid-ask spread is the difference between the highest available bid and the lowest available ask.
What are NIFTY and SENSEX?
NIFTY and SENSEX are Indian market indices that track selected groups of securities according to their respective methodologies. They are not individual stocks.
What is a Demat account?
A Demat account is used to hold securities electronically.
What is a trading account?
A trading account allows an investor to place buy and sell orders through a broker.
What is settlement?
Settlement is the process through which securities and funds are transferred following a completed trade according to the applicable market settlement cycle and rules.
Disclaimer
This article is for educational purposes only and does not constitute financial advice or a recommendation to buy or sell any security. Market prices can rise and fall, and investing and trading involve risk. Always understand the applicable market rules, costs and risks before investing.
This article is for educational purposes only and does not constitute financial advice. Please consult a SEBI registered investment advisor before making any investment decisions.